Support doubles

I have been playing support doubles with Elwood all along, but I've started playing them with Agent 99 as well. Looking back over this blog, I don't see them being mentioned, so a new entry seems to be in order.

Support doubles and redoubles arise in auctions that begin
1suit – (something) – 1major – (call < 2major);
That is, Advancer bids over Responder's 1major, and it is still possible for Opener to raise to 2major. The commonest situation is an auction that starts 1minor – (pass) – 1major – (something), but the convention still applies if overcaller bid something other than pass as long as the basic framework is still there. And it applies to auctions 1H – (pass or double) – 1S as well.

The idea is that in this situation, Opener's rebid of double (or redouble, if Advancer doubled) shows exactly three card support for Responder's major. Raising the major explicitly therefore shows four-card support.

I am not a fan of The Law, and usually don't worry too much about whether a raise shows three or four cards. But in this particular situation, the support double turns out to be a useful bid when Opener might not have anything else really clear-cut to say. Systemically, Opener might have been planning to rebid 1NT or 2NT with three-card support for Responder. After the intervention, no-trumps may or may not still be attractive, but the double conveys good information without raising the level, keeping everything in play, so to speak.

A question I asked Elwood was whether support doubles only applied when Responder's major might be four cards. The dubious auctions would begin 1m – (1H) – 1S, where Responder is promising 5+cards. A counter-question is, if not support, what might a double show? There are various answers, but Elwood favors ignoring the complications and retaining all the doubles and redouble as support. I'm going along with that.

Another question was whether support doubles were mandatory. Elwood's answer was no, but if you don't have a good descriptive or temporizing call available, you should go ahead and double.

So that's a quick run-down of support doubles. There are other ways to play, but I would recommend giving them a try. I was skeptical at first, but I find that they do come up and are useful. You can't ask more of a convention than that.