What's wrong with textbook support doubles?

Not too much. When I first put support doubles on my convention card, I played them straight out of Better Bidding with Bergen. I was never quite obsessed enough with them to say that opener must double any time he had 3-card support, and start alerting my passes as showing two or fewer. I was always mildly uncomfortable making a support double with three small or a hopelessly flat hand. When it starts 1♣-(Pass)-1♠-(2♥), there is a lot of difference between ♠Axx ♥xx ♦QJx ♣KQxxx and ♠xxx ♥KJxx ♦KJx ♣KJx. Some 4-3 fits are playable at the 2-level, but it's best if the short trump hand can do some ruffing.

Some time later, Michael (my regular partner then) and I discussed adding Snapdragon: a double by advancer in an auction like (1♣)-1♥-(1♠)-X to show a playable holding in the unbid suit, plus "tolerance," whatever that is, for overcaller's suit. We were disturbed that everyone seemed happy to leave the definition of the call so fuzzy and open-ended.

We considered trying Rosenkranz instead of Snapdragon. Rosenkranz doubles show a full-fledged raise of overcaller's suit, promising the ace or king, while an immediate raise denies a high honor. The theory is that this helps overcaller know how to defend when his side is outbid. The big downside is that the double doesn't take up any space; giving opener a cheap rebid probably costs more than you could ever gain back by defending well. (Others play "Reverse Rosenkranz" — double with the weak raises and raise with the strong ones — but that doesn't solve the problem.)

Wouldn't it be nice to clear up all three of these issues, and simplify the memory burden on your partnership, too?

Three birds with one stone

Advancer's position after (1♣)-1♥-(1♠) and opener's position after 1♣-(Pass)-1♠-(2♥) or 1♣-(1♥)-1♠-(2♥) are very similar: in both situations, you often wish to compete, but don't know which suit to bid, since partner's shape and strength are still so unconstrained.

We opted for the same simple and precise definition for doubles in both situations (and a few others):

In a low-level competitive auction where nobody has bid 1NT, advancer's or opener's 1- or 2-level (re)double...

• promises one card less than an immediate raise does, i.e., it guarantees at least a 7-card fit exists;
• it guarantees at least one of the A, K, or Q in partner's suit;
• and it shows a desire to compete.

That is, our support doubles promise Qxx or better, and our Snapdragon doubles promise a doubleton honor. (Discussion point: some of my partners like a 2-card double to be Ax or Kx, not Qx.) This sharpens up the meaning of the support double and avoids some of the disasters that are caused by hopelessly weak trump suits when pairs play "mandatory" support doubles. You only double when you have a desire to compete.

It also sharpens up the meaning of advancer's double in a different way than Snapdragon does, precisely defining your "tolerance" for partner's suit. This retains Rosenkranz's biggest benefit — sharpening your defense when opener's suit outbids you — on hands where you are likely to be outbid, and where you have an expectation of cahsing 2 or 3 rounds of your suit, or getting a ruff.

If you are a fan of Shakespeare's Hamlet, or (like me) you enjoyed Tom Stoppard's play Rosencrantz and Guildenstern are Dead, "Guildenstern" is the obvious name for a Rosenkranz-like convention.

It doesn't apply to the same hands a traditional Rosenkranz double does — those hands all raise immediately, to avoid giving opener a cheap rebid. But the claimed benefits of the Rosenkranz redouble arise much more frequently over our doubles: we are less likely to outbid our opponents when we have only a 7-card fit, and we are much more likely to want to take advantage of advancer's doubleton honour for a fast entry or ruff.

Our experience with this competitive call has been overwhelmingly positive over the years, both as a means to judge how high to compete and as a means to accurately defend. (Partner has the option to leave the double in, if he can visualize a successful defense!)

In conjunction with these doubles, we played fit-jumps by advancer, and Good/Bad 2NT by opener if the auction was past the level of 2 of opener's suit.

Basic examples

Example 1 at left illustrates one of the reasons why people play Snapdragon (or Guildenstern -- on this deal, the bidding is the same using either convention:)

West	North	East	South
			1♦
1♥	2♣	X	Pass
2♥	Pass	Pass	Pass

East wants to bid his spades. He would like a spade lead if N-S get the contract, and if West has 3-card support (or ♠Kx), spades will be E-W's best spot. But if West doesn't have support, 2♠X could be very expensive. A 2♠ bid goes past 2♥, which will be where E-W belong any time West has 6 hearts or, as here, 5 hearts but only 1 spade. East gets the best of both worlds by doubling, showing a spade suit and and his modest fit for hearts at the same time.

Example 2 is another hand where Snapdragon and Guildenstern likely lead to the same result:

West	North	East	South
			1♦
1♠	2♦	X	3♦
3♥	Pass	Pass	Pass

West shows one of his suits. East shows his ♠Ax and his willingness to play hearts or clubs with a single call. West is able to confidently bid 3♥ after South's obstructive raise. The bidding would probably be the same after a Snapdragon double, but playing Guildenstern you have a little more confidence that your ♠QJ aren't completely wasted.

Example 3 is the classic case where Guildenstern outperforms Snapdragon:

West	North	East	South
			1♣
1♥	1♠	X	2♠
Pass	Pass	Pass

If East promises a doubleton heart honor, West knows it's safe to lead a small heart at trick one. The only way to score three hearts, two diamonds, and a club is to get the hearts in the bag before declarer has time to pull trumps.

Example 4 is another situation where Guildenstern doubles lead to a different outcome than Snapdragon does.

West	North	East	South
			1♣
1♥	1♠	Pass?	2♠
Pass?	Pass	Pass

Playing Snapdragon, East would double to show a diamond suit plus tolerance for hearts. Playing Guildenstern, East is forced to pass (or bid a very subminimum 2♦), because doubling would promise a heart honour. Which is better? If N-S will sell out to 2♦ or 2♥, you'll be better placed with Snapdragon. After South raises spades, you'll be sorry if you encouraged West enough to bid 3♥, doubled and down two.

I believe that knowing what kind of trump quality you can expect from your partner is very important to these 3-level decisions, especially to knowing how likely you are to be doubled.

The fine print

There are a number of auctions that are at the fringes of the situation where classical support doubles apply:

1♣-(1♥)-X-(2♥)-X: since the negative double almost guarantees 4 spades, we use opener's double as Hxx in spades. The 4-3 fit can easily be the best place to play especially at matchpoints. It also allows you to save Good/Bad 2NT for more distributional hands without spade tolerance.

1♣-(1♥)-1♠-(2♥)-X: since responder has promised five spades, opener can raise freely with three. Therefore this double, for us, promises a doubleton honor in spades. (If you haven't explicitly agreed on Guildenstern, don't assume your partner will see this double the same way you do. Some people think this isn't a support double situation at all, and other people double with three and raise with four even though responder promised five.)

1♣-(1♠)-X-(2♠)-X: many pairs agree to use support doubles only through 2♥, not 2♠. But we like to have it still be on. It takes pressure off Good/Bad 2NT, and it helps responder decide whether to rebid a shaky 6-card heart suit at the 3-level.

1♣-(P)-1♥-(1NT)-X: discuss with your partner. It can be played either way. But I tend to assume this is penalty, not support, without an explicit agreement otherwise.

1♣-(P)-1♥-(X)-XX: Almost everyone who plays support doubles also plays support redoubles when the person in the sandwich seat makes a takeout double.

1♣-1♥-(X)-XX: Similarly, most people who play Rosenkranz doubles use a redouble the same way after responder makes a negative double. The natural alternative — a misfitting 10 points and no clear direction — is a lot like the "fuzzy" original Snapdragon, so we use this as promising a doubleton honor too.

(1♣)-X-(1♠)-X: people usually don't play this as a spapdragon/Rosenkranz situation double, since doubler so rarely has five hearts. Though if you play responsive doubles, you are quite likely to have three decent hearts and five or so diamonds when you double here. On the other hand, after (1♣)-X-(1♥), it may make a lot of sense to offer the 4-3 spade fit as a way to outbid the opponents' heart contract.

More advanced examples

Example 5 shows why I like to play Guildenstern (or regular support doubles) through 2♠, rather than 2♥.

West	North	East	South
			1♦
1♠	X	2♠	2NT
Pass	3♣	Pass	Pass
Pass

After South trots out the "bad" half of Good/Bad 2NT, showing a desire to compete at the 3-level "somewhere", North can be confident that 3♣, not 3♥, is the right call. Even if North were 3-6-1-3 it'd likely be right to offer the clubs. On the other hand, if South had doubled (on a hand like ♠x ♥Qxx ♦AQxxx ♣Axxx, North would compete to 3♥. If you only have one takeout action over 2♠, it's hard for North to confidently place the contract.

Guildenstern doubles, whether by advancer or opener, are occasionally left in for penalty, when partner knows your side has only a poor 7-card fit and good defence. More often, if the opponents bid on after you've already found out how good your fit is, you can punish them:

West	North	East	South
			1♦
X	1♥	1♠	X
2♠?	X	Pass	Pass
Pass

West has no business bidding 2♠ here. He should pass, and North's 1NT rebid should become the final contract. But if E-W compete to 2♠, North knows exactly what to do, knowing his side has no fit. During the play, it may be valuable for North to know it's safe to lead a heart, thanks to South's double promising the the ♥A or ♥K.

Our last is example is a hand where two different people want to use Guildenstern, but only one of them can:

West	North	East	South
			1♣
1♠	X	XX	2♥?
2♠	Pass	Pass	Pass

East's redouble shows a doubleton honor in spades along with a diamond suit. (I think it's reasonable to treat North has having "shown hearts" so that there is only one "unbid suit" left.) South would really like to re-redouble to show 3-card heart support. The rules don't allow that, so he has to choose between pass and 2♥. West is delighted to to know that his spades are solidified, so 2♠ on a 7-card fit looks safe. North may not like selling out, but 3♣ or 3♥ will go down, turning a possible plus (setting 2♠ one trick) into a minus.

If you give Guidenstern a try, tell me how you like it. The example deals here are all constructed by me; I'd love to feature some triumphs and tragedies from real games.

Postscript

I was surprised, back in 2013, to see the Wikipedia article on Rosenkranz doubles claim that Reverse Rosenkranz was also known as Guildenstern. I know I'm not the first person to jump on the obvious pun on the name... but "Reverse Rosenkranz" is a long-established name, and I have never heard anyone call Reverse Rosenkranz or any other convention "Guildenstern" before. A web search turned up a single article on Yahoo Voices from 2009 using the name, no evidence at all of widespread usage online or in print. Accordingly, I do not feel bad at all for promoting the name "Guildenstern" for my own Rosenkranz variation.

Note that you owe it to your opponents to give them an explanation of the bid, not say "Guildenstern" when they ask what it means. We marked it on our ACBL convention card by writing "Support X promises A, K, or Q" on the blank line at the bottom of the Special Doubles box.