Have a look at the auction. I'm sitting West, and Anna is East.
I've got the 11 point West hand. It's an easy 1♦ opener, because I have a nice 2♣ rebid. Over my 1♦ Anna replies 1♥, and South comes in with 1♠. Now it's decision time. I've got good three card support in Hearts, and a singleton, so my hand should be an excellent dummy in a Heart contract. But the problem is, I've only got three Hearts. With four of them I'd bid, but what can I do with three? If I don't show support now, I'll likely not get another chance. Could I risk raising with three? Not really. Instead, I showed my 5-4 shape with a bid of 2♣ (pass was another option).
North advanced his partner to 3♠. As Anna said afterwards, for us that hand is a clear raise to four. "Immediate 4♠". The 3♠ bid was passed round to me, and I had another decision. I reluctantly passed, but still felt a bit anxious about my three card Heart support, as we might have missed game.
What convention will let me show my three card support, and put my mind at ease? Support Doubles! On my second turn I could have doubled (instead of 2♣), to show exactly three card support.
Here's how I think Support Doubles work:
- Suppose we open and respond, and the opponents overcall (or double) at the 1 or 2 level.
- Then opener can double (or redouble) to show exactly three card support.
For example, out auction could have gone:
|1: Exactly three Hearts.|
An extra advantage of playing Support Doubles (and redoubles) are that if opener fails to make the bid, the responder knows he doesn't have three card support. And also, what else are you going to use the double for?
A final note - on this particular hand, I'm not sure the support double would have helped much, as if we get to 4♥ then the opponents bid 4♠ and make it.