DBT14: Conclusion

I've now finished all that I wanted to say on general bidding theory. It has only covered one particular aspect of bidding theory - the opening bid. And indeed it is even more specific than that, because I've been concentrating on what I would call "protecting against opponents' pre-emption", or, to give a shorter term, "description". There are other factors to consider when choosing your system of opening bids, which will often conflict with the desire to describe hands as well as possible. I'll just mention two of these things here, though of course they really are huge subjects in their own right:

• Pre-emption. As well as trying to bid our own side's hands as effectively as possible, we also want to make life difficult for the opponents. Some opening bids will be explicitly defined as pre-emptive, usually at the 2-level or higher. These pre-emptive openings tend to be fairly independent of the constructive part of the system - except of course that the more pre-emptive bids you want to use, the fewer bids you have available for constructive hands. But also, the system's "constructive" bids can have a pre-emptive effect, and this aspect has to be considered at the same time as all the issues to do with describing hands. A weak 1NT opening, for example, is an extremely good bid from the pre-emptive point of view, but weak NT systems can have descriptive problems as we have seen.
• Accuracy in uncontested sequences. As was said right at the beginning, competitive auctions tend to be more important, certainly for 1-level opening bids. But obviously there are many deals where opener's side will have a free run in the auction, and these need to be considered too. What happens in an uncontested auction will depend to a large extent on the continuations used, rather than the opening bid itself. But the definition of the opening bid can still make a huge difference to how things turn out. Most importantly, the accuracy of the continuations will depend on how much space there is: there must be enough room to look for the important information without going past the side's best contract. So again there is a conflict with trying to describe hands as well as possible - while a good description is still desirable in uncontested sequences, there is also the need to leave plenty of space for further investigation, which means that the cheapest bids will need to be used more.

Still, while you can never say that one idea is more important than anything else - it is so much more complex than that - description is the main thing that I look for in a bidding system. And it is all too easy to overlook description if you are not careful: while pre-emption is generally easy to spot, and leaving holes in uncontested sequences will also be easily picked up, protecting your side against opponents' bidding is a much more subtle problem.

Let's end by listing the main principles we've come across:

• Think-Competitive. When deciding how to arrange your opening bids, it is most important to consider what will happen in a competitive auction.
• One-Bid-Or-Two. Your system should ensure that one-bid hands are be described as accurately as possible in one bid, while two-bid hands are described as accurately as possible in two bids.
• Unbalanced-Hands-Show-Shape. You must show your suits, in order to find fits.
• Balanced-Hands-Show-Strength. The strength of a balanced hand should be bounded from below as accurately as possible.
• Homogeneity. In any particular bid, the one-bid hands should be homogeneous.

How often have you looked at your hand and thought, "I haven't described my hand as well as I would like, but I don't have a good bid available." This problem is exactly what we are trying to avoid. It doesn't require lots of artificial bidding - indeed one of the main themes is that standard natural systems are very effective. But whether your preference is for natural systems or for lots of artificiality, by following these principles as far as possible your hands will be easier to bid.

DBT13: Limited Suit Openings

Playing a Strong Club (or Strong Diamond) system means that natural opening bids can be limited to a maximum of 15 HCP or so. Since these opening bids do show shape, their maximum strength is useful information. (Even the nebulous 1D opening found in some versions of Precision at least carries the negative inference that opener does not have (or is very unlikely to have) a 5-card major, and this is a useful type of shape information since it limits how good a major-suit fit the partnership can have.) Indeed, it is often said that having limited opening bids is the real purpose behind playing a Strong Club system.

However, I would not say that it is such a great advantage. For simplicity, let's consider just the major-suit openings. The hands which are removed from 1M by the Strong 1C opening are strong and mostly unbalanced, and so these hands are usually worth a second bid in competition (though they may not be completely pure two-bid hands). So whether these hands are opened 1M or not does not really affect the homogeneity of the 1M opening bid. Responder will initially be trying to cater for opener's minimum hands, and so excluding hands of 16+ HCP from the opening bid rarely makes a difference to responder's bidding on the first round. On later rounds, opener will have had the chance to show his strength more precisely.

Of course, knowing that opener is limited is not completely useless to responder. In particular, when responder has a minimum game-forcing hand, the limited opening may be sufficient to rule out the possibility of a slam. This means that responder can take a direct route to a game contract, rather than having to leave room in case opener had a very strong hand and wanted to make a slam try. The most well-known example of this is responder's direct raise to 4 of opener's major. In natural systems this bid would only be made on a weakish but distributional hand, based on excellent trump support. But in Precision it is also possible to raise directly to game with stronger hands: those which are worth game based on high-card strength, maybe 13 HCP or so with 3-card support. By reaching your best contract in two bids you avoid giving information away to the opponents, and if an opponent has a hand which might be worth competing over the game bid, it will be more difficult for him to judge correctly now that the jump does not promise a big fit. However, responder is aiming at quite a small target here. Even opposite a very limited opening, there are not very many hands that can be certain of wanting to play in game but also fairly confident that there is no slam available. Opener may be limited in high-card strength, but he is not limited in distribution, and there are very often some well-fitting distributional hands which would make slam good. And also, if the opponents do compete, it is now opener who is disadvantaged by not knowing responder's hand.

In any case, the immediate raise to 4 is rather a special auction. There are not many other situations where the limited opening bid is immediately useful to responder. For example, if opener's LHO overcalls 3C, then responder will have to bid 3NT (say) on almost exactly the same hands as he would if the opening bid was unlimited. Of course, when holding a good hand for the bid, responder will be happier opposite a limited opening because this reduces the chance that a slam will be missed. But the point is that when opener has a weaker hand the bidding will be the same after a limited opening as it would have been after an unlimited one. When this is the case, in order to compare different systems we only need to look at the stronger hands, and ask whether they are better opened with a natural unlimited opening or an artificial strong opening.

You see the real advantage of limited openings when opener gets to make his rebid. Playing unlimited suit openings, opener's rebids have to cover all the strong hands. With limited openings these strong hands are ruled out, and so opener's rebids do not cover such a large range and can be more descriptive. But note that it's not actually necessary to remove all the strong hands in order to do this. If the natural opening contains a restricted number of strong hand types, this still makes the rebids more descriptive than a standard unlimited opening: it doesn't matter that the bid would still be wide-ranging in terms of pure high-card strength. It might make sense, therefore, to use a strong (or multi-way) opening only for hands which are particularly easy to describe by starting with a strength-showing bid (such as strong major single-suiters), and use natural openings for other strong hands.

All in all, it is not the immediate definition of maximum strength which is the advantage of limited openings. Rather, limited openings are a way of re-arranging the meanings of opener's rebids, in the hope that hands will be better defined after the second call (and with easier continuations) than if you were using unlimited openings. But of course there are very many other ways you might try to do this, and it should be better to analyse the various hand types more closely, trying to find the best way to show shape on unbalanced hands and strength on balanced hands.

Pairs who play limited openings often open lighter than is standard. That is, while they have removed a large number of strong hands from the natural bids, this is compensated by opening more hands at the minimum end of the range. However, while there is a lot to be said for opening light, I feel that the argument that light openings go naturally with a limited opening system is largely fallacious. As was said earlier, removing the strong hands from a bid does not really affect its homogeneity, since the hands removed are mostly two-bid hands. But opening light does affect the homogeneity of the bid - the hands that are added are definitely one-bid hands. So it doesn't matter whether you decide to play limited openings or not, opening light makes your bids less homogeneous. Again, limited openings may help with the rebids, but not with the initial description of the hand. So by all means play light opening bids, but you don't need a limited opening system to do so. You would only see an effect if you were prepared to play a strength-showing opening which took out significant numbers of one-bid hands, and that would mean it would have to start at about 14 HCP - maybe even less. This might be necessary if your opening bids start really light (an 8 - 13 HCP opening bid is playable whereas 8 - 17 HCP is probably not), but including lots of unbalanced one-bid hands in a strength-showing opening is not such a good idea, as we have already seen.

DBT12: Strength-Showing Openings

Nearly all opening bids give some information about strength, but here we want to look at bids which show only the strength of the hand, giving little or no information about shape. The most important example here is the Strong 1C opening in systems like Precision. Also, "natural" systems often use 2C as a strength-showing opening, but because of the low frequency of the bid and the fact that all hands opened 2C are two-bid hands, it is something of a special case and does not really define the system in the same way that the 1C opening is fundamental to Precision. We will be more interested in 1-level strength-showing openings.

The two main problems with strength-showing opening bids have already been discussed in earlier posts, but are worth repeating.

First of all, there is a danger of violating the Unbalanced-Hands-Show-Shape principle. On one-bid hands in particular, it may turn out to be impossible to say anything about the shape of the hand if you start with a strength-showing opening bid. But even on two-bid hands, while you will get the chance to say something about shape, it might not be possible to give such a complete description as you would if the opening bid had already begun to show shape information.

The second problem is that it is difficult to give a good definition of the strength of a hand in isolation, since its power depends a lot on how it fits with the other hands at the table. So, information about strength is most useful if the shape is also well defined. For this reason, if a system has a bid which limits strength very precisely, that bid will usually show shape precisely as well - as for example with a natural 1NT opening. A bid which showed a 3-point range of high-card strength without showing anything about shape would be very suspect - the upper limit on strength is almost useless, since hands can become much more powerful than expected if there is a big fit. Limited openings (ie. those where the maximum strength is very restricted) only really make sense if they show something about shape.

Information about the minimum strength is still useful, of course. As was said in "Balanced Hands Show Strength", if our hand has close to the minimum strength permitted for the opening bid that we choose to make, we can say we have "shown" the strength of the hand even if some much stronger hands are opened with the same bid. So one of the main advantages of strength-showing bids is that they satisfy the requirements of the Balanced-Hands-Show-Strength principle, for balanced hands near the minimum end of the range. For unbalanced hands the information about minimum strength is also undoubtedly helpful, but not as much as it would be if we had shown something about shape as well.

Looking specifically now at a "Strong" 1C or 1D opening bid, this typically promises a minimum of about 16 HCP, maybe slightly more or slightly less depending on how aggressive you want the system to be. Obviously, playing a Strong 1C or 1D opening has a huge effect on the other bids in the system as well, but for now we just want to look at the strength-showing bids themselves.

Such bids are unusual in terms of the proportions of one-bid and two-bid hands that they contain. Most 1-level bids are dominated by one-bid hands. But in a strong opening bid there are very few one-bid hands. Certainly, balanced hands of 16-17 HCP fall into this category. But that is about all. An unbalanced hand with this strength looks more like a two-bid hand: it may not be a pure two-bid hand, but the system really treats it as if it is, because having not shown shape with the opening bid, there is a lot of pressure to do so later. And once you start looking at even stronger hands than this, they might not like to take a second bid in competition, but they don't like to pass either. There is certainly a lack of pure one-bid hands. So these strength-showing openings have essentially the opposite problem to the very limited opening bids discussed in a previous post: while 8-12 HCP opening bids wasted space because they hardly include any two-bid hands, strong openings waste space because they hardly include any one-bid hands.

The small number of one-bid hands also gives responder an unusual problem. Suppose that he has to deal with a low-level overcall (somewhere between 1H and 2S, say). When he has a "positive" hand, good enough to force to game opposite opener's known strength, things are generally fairly easy. But more interesting is when he has a slightly weaker hand, a "semi-positive". These are not good enough to force to game immediately, so they have to be bid carefully, not going past the best part-score. Much of the time, it will be best to pass and wait for opener to describe his hand. However, since opener can occasionally have a one-bid hand, passing may result in the overcall being passed out. So responder is forced to act on a semi-positive hand if he wishes to compete for the part-score opposite a one-bid hand.

Now, if opener actually turns out to have extra values, any action from responder effectively commits the partnership to game. So the range of strength for the semi-positive hand types needs to be very narrow - not good enough to force to game immediately, but happy to play in game if opener has any extras. This does not seem to be very efficient: you are using an awful lot of system (the semi-positive responses and their continuations) to cater for a very small number of hands (opener's one-bid hands). This takes away space that could be used for more common hand types. Well-designed systems can use transfers or suchlike to combine the semi-positives and the positives into a single bid, but you still see the problem with semi-positives when responder makes a double, or where there isn't room for transfers, or when opener is prevented from showing his hand by having to cater for responder's possible minimum.

You can contrast this with the multi-way opening bids discussed previously. The equivalent of "semi-positive" hands for Swedish Club are those hands which want to compete opposite a weak NT hand, with the auction 1C : (2D) : 2S being a classic example. This has a much wider range. At the lower end, it only needs to be good enough for game opposite the strong option, so perhaps 6+ HCP. This is almost the same as opposite a strong opening bid. But the upper limit is determined by whether it is good enough to force to game immediately, which is much higher for the multi-way opening. So these semi-positive responses, which use up most of the available space, are much better used after a multi-way opening.

Some Strong Club systems go so far as to make responder's pass forcing over certain overcalls. In a sense this avoids the problem of having a small number of one-bid hands to deal with, by requiring opener to always take a second bid. But of course this takes away one of the main advantages of strength-showing openings, which is that they describe the strength of their minimum hands (particularly balanced hands) without opener having to take a dangerous second bid.

There are also a few systems which remove minimum balanced hands from the strength-showing opening completely, perhaps putting them into a strong NT opening instead. The idea is to increase the purity of the two-bid hands remaining in the strong opening, which works well when you do actually hold one of those hands. But again, you are losing the very thing that strength-showing openings are best at, which is describing the strength of balanced hands at the minimum end of the range, according to the Balanced-Hands-Show-Strength principle.

DBT11: Breaking Homogeneity (part 2)

The main idea of the previous post was that in an opening bid, the one-bid hands should be homogeneous, whereas the two-bid hands need not be. But there is still an interaction between the one-bid hands and the two-bid hands, even if all the hand types are very pure.

Responder has to choose a call before it is known what hand type opener has. In making this choice, he will be mostly concerned with catering for opener's one-bid hand types. But inevitably, his choice of call will also affect how the auction goes when opener has a two-bid hand type. For a start, it may affect the amount of bidding space available. But also, and more importantly, responder's call provides information which hopefully will be of use when opener has a two-bid hand. In order to have the most effective methods, we would really like to arrange things so that the information responder provides in trying to cater for the one-bid hands also happens to be the information that would be most useful to opener when he has a two-bid hand.

The Swedish 1C opening is a very good example of how this can be achieved. Suppose that opener's left-hand opponent overcalls 2D. Now responder will initially play opener for the dominant weak balanced hand type, which means that the methods used will be very similar to if the opening bid had been a weak 1NT. He will therefore be bidding or doubling on the following types of hands:

• Any hand strong enough for game opposite a weak balanced hand;
• Any hand with a good long suit, wanting to play a part-score in that suit;
• A hand suitable for a double. If double is take-out this means a hand with decent values, short in the opponents' suit.

He will not be bidding on mediocre hands without a long suit: these will be passed unless they are suitable for a take-out double.

This information is exactly what opener needs when he holds a two-bid hand. When opener has a strong hand like this, it is usually more important for opener to describe his hand, rather than have responder describe instead. So opener does not want responder to bid in front of him unless he has something particularly useful to say. The main thing that would be useful for opener to know about is if responder had a good suit of his own. And as we said above, this is indeed one of the hand types that responder will be bidding with. The characteristic auction for Swedish Club is something like 1C : (2D) : 2S. Here the 2S bid simply shows a hand which wants to play in 2S opposite a weak balanced hand, but the information that responder has at least five spades is also very useful when opener is strong.

This only works because the one-bid hands in the 1C opening are so well defined. In a standard system where 1C could be a weak unbalanced hand, responder would need a rather better spade suit in order to bid safely at the two-level. But in Swedish Club any half-decent five-card suit will do, such as KJxxx. If we had to pass with this sort of holding, then not only would we have difficulty in getting to a 2S part-score when that was right, but it would also be much harder to describe the hand accurately on the next round if opener turned out to have the strong option. Note also that if responder has a hand good enough to compete over an overcall, it is almost certain to be good enough for game if opener has a strong hand - this makes the continuations very easy. In summary, the weak option and the strong option of the Swedish 1C opening go particularly well together because in each case opener wants to know when responder has a moderate hand with a good suit. Of course, responder will also be bidding with strong hands of any shape, or with a hand suitable for a take-out double; again this is useful information if opener happens to have a two-bid hand. But really you see the biggest advantages of the two-way 1C opening when responder is able to show a suit.

We can contrast this with a similar-looking two-way 1C opening which shows either a minimum hand with 4+ clubs, or a strong hand of any shape. It would be very easy to build a system around this bid. And the one-bid hands here are nicely homogeneous, so responder does not have any immediate problems. However, it does not work so well, the reason being that the hands that responder will take action on have changed. In particular, he is going to be bidding on hands with moderate club support. Knowing that responder has four clubs (say) is really of very little use to opener when he has a strong hand - he is much more interested in 5-card suits, particularly major suits. And because opener's one-bid hand types no longer promise tolerance for the majors, responder will be much less willing to introduce a major suit into the auction. While we were happy to bid 1C : (2D) : 2S on a spade holding of KJxxx opposite a Swedish 1C, we would have to pass or double if the weak option just showed clubs (unless the hand was strong enough to force to the 3-level). So opener will get much less information about the majors: information is skewed towards the club suit.

The 1C opening showing "either clubs or a strong hand" is not particularly widely played. A more popular convention is a 2C opening bid which shows either a "weak two" in diamonds or a very strong hand. This has a very similar problem. If responder plays for the dominant weak hand type, then he will want to be raising diamonds on many hands with 3- or 4-card diamond support. However, if opener has a strong hand he is not interested in 3-card diamond suits at all. Indeed, a diamond "raise" may take away space that opener wanted to use to show his strong hand. Admittedly, on any given deal responder is likely to be able to guess whether opener is strong or weak. But there is much more uncertainty than you might imagine, and the price for getting it wrong is high. Furthermore, even if responder is able to work out what is going on, the partnership agreements still have to cater for both hand types, and this reduces the amount of space you have. Really, the two hand types are not particularly compatible, with information that is extremely skewed towards the diamond suit being of little use to a strong opener.

More generally, if the dominant hand type (the weak option) shows length in a particular suit, opener is going to get lots of information about responder's length in that suit, which is only going to be of use if opener's strong options have length in that suit as well. So again we see that simple natural bidding gets this right. For a standard natural 1H opening, responder is initially trying to cater for minimum hands with hearts, but if he supports the heart suit then this is still helpful to opener even when holding a much stronger hand. A more exotic example would be a 2H opening bid which shows either a "weak two" or a "strong two" in spades: here opener would be delighted to hear about spade support no matter which hand type he has (though these transfer pre-empts are problematic for other reasons, and clearly an immediate raise could make slam tries difficult with the strong type).

If you do want a wide variety of two-bid hands, then you are much better off making the weak option nebulous, or showing a balanced hand as in Swedish Club. While clearly the Swedish 1C opening has its flaws (the main one being a lack of purity in its two-bid hands, as discussed earlier), in terms of the interaction between one-bid and two-bid hands it's really as good as you can get.

DBT10: Breaking Homogeneity

Some systems have bids which are explicitly defined as multi-way bids. Perhaps the archetypal example of a multi-way opening bid is the "Swedish" 1C opening, which shows either a weak balanced hand (11-13 HCP, say), or a strong hand of any shape (typically played as 17+ HCP). Natural systems do not use this sort of bid; however, many opening bids still contain a wide variety of possible hand types. For example, playing strong NT and 4-card majors, a 1H opening could be anything from a minimum balanced hand to a very strong 1- or 2-suiter. Clearly these are very different hand types, so the bid can be thought of as a multi-way bid in much the same way as the Swedish 1C is. The only difference is that the hand types in the natural bid are not separated by such a clear dividing line.

In either case, the important thing is to make sure that the various possible hand types go well together.

The One-Bid-Or-Two principle is very relevant here. If opener has a pure two-bid hand, then he will be able to reveal which hand type he has with his rebid. But if he has a one-bid hand, he may be unable to add anything to the initial description except to deny a hand suitable for taking a second bid. So, although responder's bids must cater for all the possible hand types opener can have, it is opener's one-bid hands which you need to be most concerned about. The opening bid must provide sufficiently good information about the one-bid hands that responder will know what to do. This does not necessarily mean that responder must be able to place the contract immediately, but he must at least be able to control the auction.

The easiest way to do this is to make the one-bid hands homogeneous. That is, while the opening bid as a whole may be a multi-way bid with a variety of different options, it is a good idea for all the one-bid hands to be covered by a single hand type - or perhaps by a small number of homogeneous hand types. The reason is simple: responder needs to know immediately what he should do opposite a one-bid hand, and a homogeneous opening bid is the best way of providing immediate information. All of the ideas about what makes a good homogeneous bid apply here.

For the two-bid hands, homogeneity is not so important: it is possible to have different rebids showing different hand types. The Swedish 1C opening is an excellent example of this. The one-bid hands are very homogeneous, consisting of a single hand type (11-13 HCP balanced), whereas there is much more variety in the two-bid hands: any shape is possible for the strong option. Many other well-designed multi-way bids work the same way: they have homogeneity in their one-bid hands, but it does not extend to their two-bid hands.

One problem with this sort of opening bid is a lack of flexibility. The different hand types are very clearly separated. So, if opener has a hand which is supposed to be treated as a two-bid hand, it is important to follow up by actually making the rebid which shows the hand. Unfortunately, as we know, not all hands are "pure" examples of one-bid or two-bid hands. A balanced 17-count is certainly not a pure two-bid hand. But if you open a two-way 1C, then this hand is treated as belonging to the strong variant. So if you are unlucky enough to have LHO overcall 2S, say, and responder raise to 3S, you will be in a difficult position. If you pass then partner will play you for a weak balanced hand, but there is no safety in making a free bid either. The lack of homogeneity between the different hand types is the problem here.

So this sort of bid works best when the "strong" hand types are genuine two-bid hands - as pure as possible. Ideally, they should either have overwhelming high-card strength (20+ HCP should ensure that the hand is a two-bid hand) or be very distributional - though in the latter case you need to be careful that you can actually describe the shape well with your rebid. (Single-suited hands are best for this.) In practice, most systems will have to allow some dubious hands into their strong options because of a lack of better places to put them, but clearly the strong option in our favourite example (17+ HCP, any shape) is already rather light, and anything weaker than this would be really asking for trouble.

Typically, if the one-bid hands are going to be homogeneous, this would mean that there is a particular hand type which responder will play opener to have until proven otherwise. We would call this the dominant hand type. Obviously the dominant hand type in the Swedish 1C opening is the weak balanced hand, but the term also makes sense for natural bids. For example, playing a standard 5-card major system, the dominant hand type in a 1S opening bid is a minimum hand with precisely 5 spades. More generally, the dominant hand type would usually be the most frequent one-bid hand type that opener can hold. We can state a general "homogeneity principle" in these terms:

All the one-bid hands in an opening bid should be as

close to the dominant hand type as possible.

The idea from a previous post that the "average" length (or strength) promised by an opening bid should be as close as possible to the minimum length (strength) is really just a special case of this. But we can now see that the average should be taken over only the one-bid hands. Two-bid hands do not need to be close to the dominant hand type, provided that they are pure two-bid hands. With an "in-between" hand you have a slight problem - it may work adequately well to treat them as two-bid hands, but it would also be helpful to have them be fairly similar to the homogeneous one-bid hands, in case the auction prevented opener from showing the precise hand type.

Bids which have a wide range of one-bid hands, or where there is no single dominant hand type, are much more problematic. But they do exist, with the most obvious example being the multi-2D opening bid. A multi-2D shows a weak hand with either hearts or spades (possibly with other strong options which are genuine two-bid hands). Although the strength promised is the same no matter which major suit is held, clearly in terms of distribution this is not a homogeneous bid. In a case like this, you have to find particular reasons why the bid "works" - why should responder be able to cater for both hand types at once? In general there is no guarantee that it will be possible.

There are a few reasons why the multi-2D is an effective bid. In particular:

• It is a pre-emptive bid, and will hopefully cause even more problems for the opposition than it does for opener's side.
• It is highly likely that responder will have at least as many cards in the other major as he does in the suit that opener actually holds. If opener has hearts and responder has 3-card heart support then the partnership should probably be playing in at least 3H; provided that responder has at least three spades as well, he will know that it is safe to bid 3H because his support for a spade suit would be just as good.
• If this is one of the rare deals where responder is actually shorter in the other major, then the opponents will almost always have a fit there and probably ought to be playing in that suit. If they do bid that suit, then this will let responder know what is going on.
• Because opener has a long major, if the hand belongs to opener's side, the most likely denomination is opener's suit. So responder will not often need to find out much more information than what opener's suit is. If opener's suit was a minor there would be much more information needed, and this would be difficult to get since you are already a step behind by not knowing what opener's suit is immediately.

But the important thing to note is that these points are very specific to the multi-2D bid. If you were to think of a different multi-way bid which did not have homogeneity in its one-bid hand types, you would have to try to find different ways to justify it. In many cases, the bid simply does not work. If you ignore the homogeneity principle you have to be very careful indeed.

DBT9: Homogeneity is Bad!

A homogeneous bid is good for giving immediate information to partner. However, you must also make proper use of your ability to refine the description of your hand later.

It would be very silly to play a system in which no hands were ever opened 1S. After all, we only have a very small number of opening bids to work with, and not to use one of them would be a terrible waste. That much is obvious. But in a similar way, suppose that in your system there are no hands which, after opening 1C, would rebid 3S after the auction started 1C : (1D) : pass : (3D). Surely that is wasteful as well. In order to make maximum use of the space available to you, you would really want to make sure that not only are all the opening bids given meanings, but also all the rebids as well.

This is why homogeneity is not always a good thing. If you tell partner all the important information with the opening bid, then that's great for helping him make an immediate decision, but it leaves you with nothing else to say later.

Of course, it is not always possible to make full use of opener's rebids. If you expect partner to pass your opening bid a large proportion of the time (as for example with a 1NT opening), you cannot expect to have the chance to rebid. So the rebids cannot be defined. Having this sort of opening bid in your system effectively decreases the total amount of space available to you. This may be a problem that you are willing to accept (I quite like natural 1NT openers myself), but it is still a problem.

The difference between one-bid and two-bid hands comes up again here. Opener's high-level rebids can only be used on two-bid hands. So, if you want to make full use of the space available in each opening bid, then these opening bids must each contain a fair number of two-bid hands.

Limiting the strength of your opening bids is bad from this perspective. An extreme example would be a 1H opening in a Strong Diamond system, which might show about 8-12 HCP with 4+ hearts. Hands in this strength range are hardly ever going to be two-bid hands. So after any reasonably high-level competition you would have to make disproportionate use of pass. The other rebids may get used very occasionally - and would therefore be very descriptive when they do come up - but the vast majority of hands will not be further described. To put it another way, there will be fewer sequences in your system available for the genuine two-bid hands (because none of them start with 1H), so these will not be described so well.

In contrast, a "standard" 5-card major opening, with a range of 11-21 HCP or so, makes much fuller use of the two-bid sequences (arguably too much). The beauty of this bid is that it is on the one hand a nice homogeneous bid (partner knows about the 5-card suit immediately) but there is also plenty of potential for making descriptive rebids.

It's important not to confuse this with arguments about the frequency of the opening bid. Indeed, trying to analyse systems by looking at the frequencies of their opening bids is very unreliable. For example, suppose you were to play a 1C opening showing a balanced hand with 10-13 HCP. Then this has a frequency of about 15% in first seat, much higher than standard systems which typically have 1C openings with a frequency of 10% or less. However, this 1C consists of a single hand type with no two-bid hands, and so hardly any of opener's rebids are utilised. So we might say informally that "you are not opening 1C enough", but really this argument is not about pure frequency at all, rather the number of different hand types in the opening. You could easily add, say, all 20+ HCP hands to this 1C opening. Indeed this could result in quite a respectable system, as we shall see later.

DBT8: Homogeneity is Good

Let's consider a particular opening bid, say 1H. A bidding system will typically require somewhere between 5% and 10% of hands to be opened 1H in first seat. Of course, if you were to choose 5% of hands at random, they wouldn't make a very good 1H bid: we have to choose them so that the opening bid provides useful information to partner. Particularly useful is if all the hands which are opened 1H share a property (or properties) in common, as then partner will be able to make deductions without having to wait for further clarification.

For example, suppose that our 1H bid promised exactly five hearts. Then if partner holds an average hand with four hearts, he can deduce that it is likely to be safe to compete to the three-level in hearts. This is based on the Law of Total Tricks, which admittedly is far from infallible, but is a good guide when you know exactly how many cards your partnership has in the suit.

It is fairly unusual to have a bid which shows exact length in the suit. More common would be a bid which shows five or more hearts. In this case, partner would still be justified in bidding to the three-level on an average hand with four hearts, but now if opener turns out to have more than five hearts there is a fair chance that bidding only to the three-level would be under-competing the hand. Similarly, if the 1H opening could occasionally be only a four-card suit, if responder still bids to the three-level there is a danger that this will be too high. Of course, there are many other factors which affect how high we should be competing, but trump length is very important, and so the more specific the information responder has about suit length, the better his chances of getting the decisions right. This is just part of the obvious general principle that a homogeneous bid - one where all the hands opened with that bid have some property in common - is good for providing information to responder. And the more specific the property is, the better.

Let's think a bit more about this 1H bid showing length in hearts. As mentioned already, in most systems the bid does not show exact length: rather there is a range of possible lengths. In this case, there are two properties of the opening bid which become important:

• The minimum length promised by the opening bid; and
• The average length promised by the opening bid.

For example, in Acol, where the minimum length for a 1H opening is 4 cards, the average length is close to 5. (I'm deliberately being a bit vague about what I mean by "average", but usually this would be interpreted as the arithmetic mean.) But other systems can have very different numbers - even if you consider only 4-card major systems, there is a lot of variety in how often 1H is opened on a 4-card suit.

This poses a problem for responder. If you are in a position where you have to make a decision without further help from opener, then you will have to decide - do you play opener for the minimum length, or for the average length in hearts? Playing opener for his average length will be right most of the time, but if he turns up with fewer cards than the average there is a danger that the partnership will be too high, or even playing in the wrong denomination. Whereas, if you anticipate opener holding his minimum length, you may very well be under-competing. There is not really any good solution to this, you are forced to hedge your bets.

But this is much more of a problem for some systems than for others. The key is this:

It helps to make the minimum length for your bids
as close to the average length as possible.

This is how you avoid responder's problem of what to play for.

And this explains the big advantage of playing 5-card majors.

5-card suits are much more common than 6-card or longer suits. So when you open 1H or 1S showing 5+ cards, the average length is still close to 5. The distinction between minimum length and average length therefore does not worry responder: he can happily play opener for a 5-card suit. From the point of view of homogeneity, a suit opening which promises 5+ cards is about as good as you can get, short of showing the exact length.

4-card opening bids are much worse in this respect. Assuming that you still open 1H or 1S when the major suit is five cards long, the average length for these opening bids is going to be closer to 5 than 4. This means that responder will find it difficult to judge hands with support for the major. (Of course the corresponding advantage that these systems have is that you get to find major-suit support more often in the first place.)

The worst possible case is if you play 4-card majors, always open your longest suit, and tend to open the lower of two 4-card suits. Then virtually the only time you open 1S on a 4-card suit is when you have precisely 4=3=3=3 shape. Here the average length is over one card more than the minimum length. Indeed, I would hardly say it is a homogeneous bid at all: it basically shows either a 4=3=3=3 hand or 5+ spades, and this is very bad news for responder since the first hand type is not particularly great for playing in spades at all, whereas the second type is excellent for spade contracts. How is he supposed to know what to do with spade support? I hope you would not be so foolish as to play this system - the balanced hands are so rare that it's much better to take them out of 1S somehow and guarantee five cards as the minimum. If you're going to play 4-card majors, you need to open them on four cards as often as you possibly can. This brings the average suit length down much closer to the minimum. This is another good reason why if you are playing a strong NT, it makes sense to open 1H or 1S on minimum hands with a 4-card major even if holding a longer minor.

The same principles apply when we are considering the strength promised by an opening bid, rather than the length. That is, we would ideally like to have a precise description of strength, but if forced to use a relatively wide range, we really want the minimum to be as close to the average as possible. For an opening bid which promises 12+ HCP or thereabouts, this usually happens fairly automatically, since hands with higher HCP values are less frequent. But it doesn't always work that way. For example, if you play a short 1C opening and a weak NT, the 1C opening is very often a "strong NT" hand type. This means that the average strength (perhaps it is more helpful to think of the mode here) is not so close to the minimum. Of course this analysis is rather too simplistic, as there are some definite advantages arising from the "multi-way" nature of this bid - opener is known to have either real clubs or extra strength - but having the most common hands so far away from minimum strength should still be a cause for concern.

DBT7: Balanced Hands Show Strength (part 2)

Some systems are very good at showing strength on balanced hands. For example, many Italian pairs bid balanced hands something like this:

• 12-14 HCP: open 1-of-a-suit (usually 1C)
• 15-17 HCP: open 1NT
• 18-19 HCP: open 2D (showing exactly this hand)
• 20-21 HCP: open 2NT
• 22+ HCP: open 2C

Here, the strength of a balanced hand is never more than 2HCP above the minimum promised by the opening bid, even for very strong hands. This is taking the Balanced-Hands-Show-Strength principle to extremes, and of course most systems will not make it such a high priority. But even if you do not build your entire system around showing strength on balanced hands, you should still be aware of the hands where it is most important, which are those with a strength of about 15 or 16 HCP. On weaker hands there is rarely a problem, because unless you play very light openings, those hands will not be significantly better than a minimum opening bid. And once you increase the strength to 17 or 18 HCP, you start to reach hands which are usually good enough to take a second bid (though they can still be a problem if the intervention is high enough, as with the example in the previous post). So it is the hands in the middle, about 15-16 HCP, which are most likely to cause a problem.

Most weak NT systems violate Balanced-Hands-Show-Strength on these hands. Here is the very first example from part 2:

S KJ7
H KQT4
D 97
C AQ53

When we play a strong NT we can open 1NT and this is a very pure one-bid hand. When we play a weak NT we have to open 1C or 1H, and now it is a nightmare hand. Supposing for the moment that LHO overcalls 2S, what is going to happen now?

Well, if 2S gets passed back to us, we will have to pass it out. This hand is nowhere near worth a second bid over a 2S overcall. So it is up to partner to do something if he wants to be in game opposite a 15-16 HCP balanced hand. The problem is, if partner does do something, and finds that you actually have a weak unbalanced hand after all, you will not always have a good fit at the three-level. And if he does bid at the three level, are you invited to bid game with a balanced 15-count, or is it merely competitive? Responder really needs to have ways to do both things, which puts a lot of strain on your system.

This assumes that partner passed at his turn. But even if he made a bid, or perhaps a negative double, there still may not be any safety in us taking a second bid. In these situations, weak NT players often use opener's double to show a balanced hand (and at least 15 HCP). This gets the strength across, but it is rather dangerous since there is no guarantee that it is right for us to compete. If we had observed the Balanced-Hands-Show-Strength principle, and described the strength of these balanced hands already, then the double could be reserved for hands which genuinely wanted to compete.

People that do play Acol or K-S, or similar systems, will accept these disadvantages and hope to gain instead on other types of hands. The weak 1NT opening itself has many advantages, being both very descriptive and also a good pre-emptive bid. It is particularly useful in first seat, and when the vulnerability is favourable, because of the pre-emptive effect. But my feeling is that in other positions it comes nowhere near making up for failing to show strength on the stronger balanced hands.

But it is possible to play a weak NT without violating the Balanced-Hands-Show-Strength principle. In Fantunes, Millennium Club and Nightmare, a 1C opening shows a better-than-minimum hand: 15+ HCP if balanced and not much less than that if unbalanced. And so opening 1C does show the strength of hands in the 15-16 HCP range very well. It turns these "strong NT" hands back into pure one-bid hands, which is what they naturally are. Also many Strong Club systems do a similar thing (though they may promise slightly more strength with the 1C bid, which puts pressure on hands with 15 HCP). If you want to play a weak NT without giving yourself huge problems on the "strong NT" type, you should play a system like this.

DBT6: Balanced Hands Show Strength

This is the companion to Unbalanced-Hands-Show-Shape. Showing shape is always a good thing, because fit is all-important in competitive auctions. But, as explained in that post, there are various reasons why showing shape is more important with unbalanced hands. In particular,

• When you hold an unbalanced hand, your side's fit is most likely to be in your own long suits, so you need to tell partner what your long suits are. Whereas when you hold a balanced hand, your side's fit will be in partner's long suit.
• Holding an unbalanced hand increases the chances of the deal being a big fit, and so increases the chances of there being a high-level competitive auction.

At the same time, it is more important to show strength when you hold a balanced hand than an unbalanced one. Before going into the reasons for this, we need to look at exactly what it means to "show" the strength of a hand.

The problem with trying to evaluate the strength of a given hand is that everything depends so much on the context - there is a big difference between "offensive strength" and "defensive strength", and both of these are significantly affected by how well the hand fits with partner's. Even so, we have to be able to speak about the "strength" of an individual hand. Without wanting to go into detail about hand evaluation (personally I think that coming up with detailed formulae is neither worthwhile nor particularly interesting), everyone would at least agree that the strength of a hand depends on both the high cards and the distribution. But the value of high cards depends much less on the context than the value of distribution, and so when we talk about "showing strength" this will mostly based on high-card strength.

Now clearly, a 1NT opening bid with a narrow range, such as the Standard American 15-17 HCP, does show strength very precisely. The minimum strength and the maximum strength are both useful pieces of information for responder. However, a bid which has a much wider range, like a Standard American 1C opening (showing 12-21 HCP or so) is still considered to be a good description of strength for hands which are near the lower end of the range. The reason is that partner will play you for a hand of minimum strength unless you do something which shows otherwise. So the fact that you have at least 12 HCP is very useful information for partner - it means that he can bid a game if he holds a similar amount of strength himself - whereas the lack of a maximum is not a problem because he was not going to play you for much more than the minimum strength anyway. This works fine, provided that there is enough space to tell partner when you do in fact have a better-than-minimum hand. (In the case of a 1NT opening bid you obviously don't have enough space to do this, so it is necessary to have a narrow range.)

So, the statement of our new Balanced-Hands-Show-Strength principle is that when we have a balanced hand, we should try to make sure that partner's idea of our minimum strength is as close to the true value as possible.

Why is this so important? Well, as mentioned above, if we have substantially more than the minimum strength we have promised, then partner will not play us for a hand that strong. This would not be a problem if we could make a rebid which showed our extra strength. However, the important thing about balanced hands is:

Balanced hands are not two-bid hands.

As was said in the discussion of One-Bid-Or-Two, the stronger and more distributional a hand is, the more likely it is to be a two-bid hand. Since a balanced hand is, by definition, not at all distributional, it would have to be extremely strong in order to be a genuine two-bid hand.

S QJ9
H AT2
D AK5
C KQ92

This hand is a full 19 HCP, but if you open 1C and the opponents reach 3S before you have the chance to rebid, you are faced with a difficult problem. Doubling or bidding 3NT could very easily be wrong, showing that this is not a genuine two-bid hand. But neither is it safe to pass. The problem is precisely that we have not shown strength with the opening bid - partner could easily have enough for game, but he would have no way of knowing.

Fortunately, if we have a very strong balanced hand like this one, high-level interference is quite rare. But still, it's extremely difficult to cope with when it does happen, if we have not already shown strength. With an even stronger hand we would probably have to take a second bid regardless - there comes a point when any type of hand is strong enough to be a two-bid hand - but the vast majority of balanced hands are one-bid hands, and for those we really want to show strength immediately.

DBT5: Different Ways of Showing Shape

As explained in the previous post, showing shape with the opening bid is very important, particularly for unbalanced hands. The question is, what is the best way to do this? The most common approaches are either to show length in a particular suit, or to show a balanced hand (i.e. length in every suit). "Natural" systems use only these two methods, whereas other systems may show shape in more unusual ways.

It's important to remember that the reason we show shape is in order to find a fit. (Indeed, we need to be able to find out both where the fit is and how good it is, though these things generally come together.) So, the best shape-showing bids are the ones which maximise partner's chances of knowing (or finding out) what our fit is. Some bids which appear to show shape are actually not particularly helpful for finding fits. The most extreme sort of example is if your system has a bid which shows a hand of 5-4-3-1 shape, but does not indicate which suit is which. If your only aim was to reveal the complete shape of the hand then this would be a fine way to start - later bids could reveal the order of the suits - but for finding fits quickly it's absolutely hopeless.

The standard method of bidding unbalanced hands is to start by bidding your longest suit. One obvious reason why this is sensible is that, a priori, this suit is the one most likely to be your side's best fit. However not all systems work this way. An alternative is "canapé" style, where we bid the second-longest suit if holding a two-suited hand. Pure canapé is rather uncommon, but many systems vary between opening the longest and the second-longest suit depending on the hand type.

The obvious problem with canapé is, how are you going to find out whether you have a fit in your longest suit? You can't rely on partner to bid the suit, because your side might have a fit there even if he does not have a very remarkable holding. Essentially, the only way you can discover a fit in your longest suit is if you are able to bid it yourself. And this may not always be possible. Unless you have a pure two-bid hand, you might not be able to take a second bid at all.

But this doesn't necessarily mean that canapé is a bad idea on one-bid hands. Take a hand like this, for example:

S Q4
H KQ52
D 82
C AJ984

Would you rather open this 1H, showing 4+ hearts, or 1C, showing 4+ clubs? There is a lot to be said for the 1H opening. If partner will expect four cards in whatever suit you bid, then the 1H opening is no less descriptive than 1C. And major-suit fits are more important than minor-suit fits. If 1C did not promise four cards (say you were playing a more artificial system) then it would be even more clear that 1H was a better initial description of the hand. The problems, if there are any, come when you try to refine the description of your hand with a rebid: you would like to be able to show both of your long suits. But since this is a pure one-bid hand, you only expect to get one chance, and so it is reasonable to bid on the assumption that you will only get to show one suit. In that case, showing four hearts must be at least as good as showing four clubs.

So, concealing your longest suit works fairly well when you have a pure one-bid hand, provided that the bid you choose to make is still a good description (if you were concealing a five-card major, it would be much worse). The real problems with canapé come when you have a hand which may be worth a second bid, and particularly if it is neither a pure one-bid hand nor a pure two-bid hand, but somewhere in between.

S 5
H AK93
D QT4
C AQJ62

You open this 1H, LHO bids 2S and it is passed back to you. Now you certainly don't want to pass, but what do you do? Well, this would depend on your methods, and there are many different possibilities, but nothing looks particularly attractive. The natural method would be to show the club suit directly, but this gives up on playing in diamonds or defending spades. Alternatively you could double, if this is defined as take-out, but now you haven't revealed your longest suit and so your continuations will be hampered by having to find this out. You also have the difficulty of trying to distinguish this type of hand from one with five hearts, if those are also opened 1H. Indeed, it seems that your initial shape-showing bid is not helping you at all: if you had opened with a strength-showing bid like a Precision 1C, then a take-out double of 2S would describe the shape of this hand equally well as anything you can do after opening 1H.

Similarly, if the opponents instead overcall in diamonds, there is still a fair chance that we have a fit in clubs, but it is dangerous to look for one because if a fit is not found then we have nowhere else to go.

This exposes a basic problem with not showing your longest suit the first time: if you get the chance to take a second bid, then you will not know what to do. On the one hand, you would like to show your longest suit, because this is by far the suit most likely to be a fit: but on the other hand, you can't commit to playing in your longest suit, because there is no guarantee that it will be right.

And so, if you see a pair playing canapé, or other methods involving not showing the longest suit with the opening bid, they will generally do so only with

• pure one-bid hands, where the problems with taking a second bid are not important; and/or
• pure two-bid hands, in cases where it is almost certain that a good description can be given with the second bid.

For example, playing strong NT and 4-card majors, it is reasonable to open 1H with a hand like my first example above. But we would never open 1H on a similar hand with an extra king, because then it might be worth two bids. (In fact it might well be opened 1NT in that case, in order to turn it back into a one-bid hand.) Similarly, canapé often goes together with a strong club, where the natural suit openings show fairly weak hands, which are unlikely to be worth more than one bid. Though here, hands near the top of the range for a limited opening can still be a problem.

The more traditional method of opening the longest suit really comes into its own on these difficult "in-between" hands. If the auction goes in such a way that it is too dangerous to take a second bid, then at least we have already shown the most important feature of our hand. Whereas if we do get another chance, we now have plenty of flexibility in deciding what is the next most important feature to show. Flexibility is the key: having shown the longest suit already, we could later decide to bid a second suit naturally, but we could also choose to double for take-out, or bid no-trumps, or repeat the first suit, or even make a conservative pass. If we had bid some other suit first, then these options might still be available, but they would not all tell partner about our long suit, so we would have failed to give such a good description of the hand in our two bids, as demanded by the One-Bid-Or-Two principle.

Of course there are other good reasons why you might want to open the longest suit. For example, it increases the average length shown by your opening bids. This is part of a much bigger topic on homogeneity that I will come to later.

DBT4: Unbalanced Hands Show Shape

Let's restrict our attention to constructive opening bids (as opposed to pre-empts) and consider how to define these in order to describe hands as well as possible. For the moment we'll ignore the main other desirable quality for opening bids, which is that we want them to be obstructive to the opponents.

Bidding systems generally define constructive opening bids in terms of just two things:

• The shape of the hand (ie. the lengths of each of the suits); and
• The overall strength of the hand.

Of course, by describing only these two things we are leaving out much of the detail of the hand, since we will not show anything about how the high cards are distributed amongst the suits. But because we have so few different opening bids to choose from, it is simply not possible describe that sort of detail.

Indeed, even when we restrict attention to shape and strength, there is only a very limited amount of information that we can convey with the opening bid. So we have to decide what is most important. And for unbalanced hands, it turns out that showing shape is most important. That is, while any opening bid will generally tell you something about strength (a standard opening bid might promise a minimum of about 12 points), your main concern should be to describe shape as effectively as possible.

The reason for this is that, according to the Think-Competitive principle, we have to anticipate what is going to happen in a competitive auction. And in competitive auctions, fit is all-important. This is most famously stated in the "Law of Total Tricks": if our side is bidding one suit and the opponents have bid another, then the decision as to whether to compete over an opponent's bid should depend almost entirely on how many cards we have in our suit and how many cards the opponents have in their suit. Strength hardly makes any difference to this decision (though of course it may be important if there are other decisions to be made, such as whether to bid a game). So if we are to get these competititive auctions right, it is vital that we know how good our fit is. In order to do that, we have to show shape.

When we hold an unbalanced hand, this increases the chance that we have a big fit - and also increases the chance that there will be a high-level competitive auction. Furthermore, if our side does have a big fit then it is likely to be in one of our long suits, and so it is essential that we tell partner which suits we have. This gives us our new principle: "Unbalanced-Hands-Show-Shape".

For one-bid hands, then, the situation is very simple: we have to try and describe the shape of the hand as well as possible with the opening bid. In this respect, opening bids which promise long suits are very good: a 5-card 1S opening is an excellent description of a hand which has five spades. The difficulty is in being able to give good descriptions for as many different types of hand as possible, and for one-bid hands this should be done on the assumption that we will only get one chance.

For two-bid hands things are more complicated. We must still try to show the shape of the hand, but now we are going to get two chances to do this. Perhaps this means that we do not need to worry about showing shape so much with the opening bid?

In fact this is unlikely to be true. It will usually take two shape-showing bids to describe the shape of an unbalanced hand well. For example if we hold a two-suiter, we need one bid to show the first suit and another to show the second suit. With a more flexible hand such as

S AQT53
H KJ3
D 7
C AK64

we can show our long suit (spades) with the first bid and then hopefully double for take-out the next time (if opponents bid our short suit). Particularly with these flexible hands, a double is often by far the safest action in a high-level competitive auction, and so if we had not shown our long suit with the first bid, we would be struggling to show it later.

Occasionally, though, we come across a hand like this:

S AKJ9532
H A2
D 4
C KQ9

Suppose we start by showing shape on this hand with a 1S bid, and the opponents bid up to the 3-level or 4-level. This isn't a disaster, since the spade suit is easily good enough to rebid. But rebidding spades doesn't quite express how good this hand is. Look what happens instead if we are playing a strong club or multi-way club system and open this hand 1C. Again, the excellent spade suit means that we have a comfortable rebid even if the bidding comes back to us at a rather high level. But, having rebid 4S or whatever, we now feel that the hand is described perfectly: we have described the shape and the strength. So this particular sort of unbalanced hand - a strong major 1-suiter - is actually very good for strength-showing openings. This can be viewed as being an exception to the Unbalanced-Hands-Show-Shape principle, but really what is going on is that it is a pure two-bid hand and you know you will be able to show shape very precisely with your second bid. Note that a 1-suited hand with a long minor is not quite so good, because it may not be advisable to bid your suit on the next round if this would result in missing 3NT.

DBT3: One Bid or Two? (part 2)

In the previous post, our One-Bid-Or-Two principle was a guide for what to open with a particular hand. But we can also write down a similar One-Bid-Or-Two principle which applies to entire bidding systems. It is, again, very simple:

You should arrange your opening bids in such a way that:

• one-bid hands are described as accurately as possible in one bid;
• two-bid hands are described as accurately as possibly after two bids.

To put it another way, it is perfectly acceptable to have a relatively poorly defined opening bid in your system, intending to clear things up with the rebid. But this only works if the hands which need clarification are genuine two-bid hands. Otherwise there will be trouble.

I hope that the One-Bid-Or-Two principle sounds reasonable. However, it is certainly not the only thing we need to worry about. For instance, it may be more important to use the available bids to pre-empt the opponents. This is often in direct conflict with the desire to describe our hands as well as possible. Since we only have a limited number of bids available, there will have to be compromises made. But One-Bid-Or-Two should always be one of your main considerations, and I will spend a lot of time discussing it because it so often seems to be neglected.

So far I haven't said anything about how the hands are going to be described, only that they should be described as well as possible. In the next post I'll start discussing the various ways you might try to describe your hands.

DBT2: One Bid or Two?

Suppose you deal yourself the following hand:

S KJ7
H KQT4
D 97
C AQ53

Let's say you're playing a strong no-trump opening, and so you open 1NT. Now suppose LHO bids 2S. and this is passed back to you. What do you do?

Pass looks pretty clear, doesn't it?

Suppose instead that LHO had overcalled 3S, would that make any difference? Well, no, now it would be insane to do anything other than pass. What about 4S? Again pass is obvious.

Of course the reason that you pass so happily in each case is that the opening 1NT bid has already described your hand very well. If it was correct for your side to do something, then your partner should have done it already. So I call this hand a "one-bid" hand: you're not planning to take a second bid (or make a double) unless forced to do so.

Contrast this with the following hand:

S AQ9832
H AKJT4
D 8
C 4

You deal and open 1S. LHO overcalls 2D and it comes back to you. Now maybe your choice of bid is not completely obvious, but what is clear is that you must show hearts in some way, describing your hand as a good two-suiter. Similarly if LHO had bid 3D, you would still rebid hearts at your turn. An if LHO had bid 4d? It still must be right to bid hearts. You can probably see where I'm going with this: this hand is a perfect example of a "two-bid" hand.

Perhaps this looks like a completely trivial observation, but I've found that the difference between one-bid and two-bid hands is fundamental to just about everything to do with the theory of opening bids.

Obviously the two hands above are very "pure" examples, in that the decision as to whether to take another bid was pretty much independent of the level of the opponents' intervention. More often you will be faced with a hand which is happy to take a second bid if the opponents interfere at a low level (particularly if they bid our shortest suit), but which is not good enough to take a second bid if the intervention is sufficiently high.

Note also that whether a hand is a one-bid or a two-bid hand may depend on the bidding system. For example, if you held the first hand and were playing a weak no-trump, you would have to open it 1C (or perhaps 1H), but now you would not feel that you had really described your hand until you had rebid in no-trumps. Even so, it is often helpful to describe hands as "one-bid" or "two-bid" hands independently of the system being used. My second example is probably worth two bids no matter what system is being played. Whereas a flat 12-count is only ever going to be a one-bid hand in competition. Clearly, the important factors are the shape and the strength of the hand. The stronger or more distributional a hand is, the more likely it is to be a two-bid hand.

How should all this affect our choice of bid? I think the conclusion is fairly obvious:

• When you have a one-bid hand, you should aim to describe it as well as possible in one bid.
• When you have a two-bid hand, you should aim to describe it as well as possible in two bids.

Of course, this may be too simplistic in many cases. For instance, if you have one of those hands which may or may not be worth a second bid depending on what interference you get, then you will want to describe it quite well with the first bid, while still leaving yourself easy ways to refine the description with a rebid if the auction allows. Still, the basic principle is very important. I will refer to it as the One-Bid-Or-Two principle.

Here is a very simple example: suppose you have to choose an opening bid with the following hand, playing a natural 5-card major system:

S AKJ73
H J4
D -
C KQJ972

Your choice is between 1C and 1S. Since 1S promises five cards in that suit, whereas a 1C opening only promises three, it might seem like the 1S opening is a better description. But that ignores the fact that this hand is very definitely a two-bid hand, and so you should choose the opening bid which allows you to describe the hand as accurately as possible with two bids. The way to do this is to open 1C: you will virtually always be able to rebid comfortably in spades, and this will inform partner that the club suit is longer. (If the spade suit and diamond suit were switched then it would not be so clear, since while the hand would still be a two-bid hand, it might not be so easy to give a good description with those two bids.)

Finally, is there such a thing as a three-bid hand? Well, not really. That would only make sense if the opponents interfered over our opening bid and then interfered again over our rebid. Since opponents don't tend to do that very often, it's not something which is very important to consider. Indeed, if the opponents are going to interfere then the worst case is when they reach their highest level immediately. So the important thing is whether a hand is good enough to take the second bid. Hence the "One-Bid-Or-Two" distinction.

David's Bidding Theory: Introduction

Bidding theory is a huge subject because there are so many different auctions possible. If you're given the first few bids in the auction, you can always ask the question, what are the best meanings to give to the various possibilities for the next call? Depending on what the auction has been, it may be that natural continuations are best; or maybe you should make use of some artificial ideas such as transfers or relays or multi-way bids - or anything else you can think of. Serious partnerships could spend a huge amount of time deciding what they should do in all these different situations.

But there is one situation which is much more important than any other. That is, how will you define your opening bids? This is the aspect of bidding theory that I will be taking about in this series of posts. The opening bids are essentially what determine your "basic system", and I will be discussing what makes some systems better than others.

Let's start with one of the commonest mistakes made by amateur bidding theorists.

When you open the bidding, you can't be sure how the auction will turn out. But there are two main possibilities: either your side will have the auction to yourselves, or the opponents will come in and you will have a competitive auction. Which of these possibilities should you be more worried about?

Well, perhaps the correct answer is "it depends", but most of the time there is no doubt: competitive auctions are the important ones. The reason is simple: it's harder to reach the right contract in a competitive auction, because you have to worry about what the opponents are doing, and you usually have less space available. So, if your system works reasonably well in competitive auctions, it's can't be too bad when the opponents are silent. The converse is not true: if you come up with a set of responses which assume the opponents will be silent, it might all fall apart if they start bidding. Also, competitive auctions tend to be faster than non-competitive ones. If the opponents do not bid then a poorly defined opening bid can be corrected by a subsequent rebid, but if the auction is competitive then by the time you get to make your rebid it may already be too late.

The only time you might be more worried about constructive auctions is when the opening bid itself consumes a lot of space - particularly if it promises a good hand, as with a natural 2NT opening bid.

Admittedly, if you look at a book which describes a particular system, you will probably find that most of it is devoted to non-competitive auctions. That is the way it should be, since you can't play a system unless you know what to do in constructive auctions. Even so, it's the competitive auctions which will decide whether the system is a good one or not. I'll call this principle "Think-Competitive".

No doubt if you're reading this you will have known this principle already. But ignoring competitive auctions is a fairly easy mistake to make. I've often seen systems suggested where a 1C opening is made on a variety of possible hands, and the idea is to reveal which hand type is held with the rebid. Such systems often violate the Think-Competitive principle: if the opponents interfere at a high level, it may be too dangerous for opener to describe his hand. It is of course possible to create a workable multi-way 1C opening, but you have ensure that you can cater for all the various hand types in competition. More on this later.