It seems logical to discuss support doubles after finishing negative doubles. They are both actions that let you convey multiple pieces of information to partner with one bid, saving a level of bidding space. The other thing they have in common is that the advantage achieved by those two actions could not be enjoyed without the opponent’s assistance and cooperation. Thanks for the overcall! As opener, after 1d/p/1h, I often find myself internally cheering for RHO to make an overcall. Without an overcall, I am going to have trouble finding out if my partner holds 4 hearts or 5 hearts, since “pass” takes away my support double. If you are defending in that sequence, do you ever think “should I pass on this worthless overcall and take away their support double?” To my opponents who love to make aggressive and questionable overcalls, keep it up, we couldn’t get to our best contracts without you!
Unlike the negative double which is always made by responder, the support double is always made by the opening bidder at his second opportunity to bid. The bidding goes 1d/p/1s/2c/?: You hold Axx, Kx, AQxx, xx. You show 3 card support for partner’s spades by doubling 2 clubs. This bid does not limit the size of opener’s hand, it merely shows 3 card support, denies 4 card support and transfers control of the hand to responder. If responder has a 5 card spade suit you are going to play in some number of spades, depending on the size of responder’s hand. If he has only 4 spades, he can try for no trump or play the 7 card trump suit.
Suppose on the same bidding you held Axxx, Kxx, AQxx, xx. You now need to tell responder a different story; that you have 4 card support. With this minimum hand you would do that by bidding 2 spades over the opponents 2 club overcall. Note: here you can also show the size of your hand. With 12-15 bid 2 spades, with 16-18 bid 3 spades and with 19+ bid 4 spades.
Assume we change the bidding to 1d/p/1s/x: With three card support as in my first example, make a support redouble, it means the same thing as “double” in our earlier context. If you have the second hand, simply bid 2 spades to show 4 card support. Support Doubles or Redoubles Must be Alerted.
What do you do if you do not have either 3 or 4 card support. If you don’t have a strong hand you can always pass, partner will have another bid. If you have some defensive tricks and are strong in the opponent's overcalled suit, you must pass and hope that partner will double back in so that you can pass his double for penalties.
Is making the support double or redouble obligatory with 3 card support? I think the best rule is to play that you must show the support if you have it. Max Hardy says that opener has an obligation to double or redouble if he has a 3 card fit for partner’s bid suit. One advantage of playing support doubles “mandatory” is that you know when opener passes he has 2 or fewer cards in your bid major. I believe that with this understanding it is appropriate to alert the pass as denying support.
Use support doubles only when you do not know whether responder has a 4 or 5+ card suit. If responder’s bidding clearly indicates that he has either a 4 card suit or a 5+ card suit, then support doubles are off. So if the bidding goes 1d/1h/1s/2h/, we know that partner by bidding his spade suit, rather than making a negative double, is showing 5 spades, so a double of 2 hearts at this time would be for penalties! I credit my partner, Howard Christ for this analysis, but I like it.
If you agree to play support doubles (as each of your should) it is important to decide how high to play them. Here is a workable rule: Play support doubles on every conceivable auction up to the level of 2 of responder’s bid suit.
Bob Scarbrough and I were playing recently when Bob opened his hand with one diamond. I responded one heart, and my LHO bid one spade. Bob held Qx , QJx, AQJxxx, xx and choose to rebid his 6 card minor suit and eschew the support double. As it turns out, I have a 5 card heart suit and we can compete effectively in hearts. I tactfully whispered “Support Double.” Bob replied, “Do some research, I want better authority.”
Mike Lawrence in his book “Double” (2002) gives us this hand. 86, KQ8, J10, AQ7842. The bidding is 1c/p/1h/2d/?. Mike says don’t rebid your 6 card minor, you must make the support double. If you have a really big hand you can rebid the minor on the next round. Max Hardy in his book “Advanced Bidding for the 21st Century” (2000) on similar bidding shows K84, 84, AKJ1062, J8. and says make a support double, it is more important to show 3 card support for spades than your 6 card diamond suit.
For the record, the controversy is still unresolved, as Bob maintains that Mike is too old and Max is dead. It is nimble thinking like that keeps us going! Who can quarrel with that cogent analysis?