Zelandakh, on 2013-January-28, 09:44, said:
I notice that after 1♣ - 1♥; 1♠, pretty much everyone is rebidding 2♥. One of the things I have been taught is that you should only rebid your suit when Opener showed 2 suits if you are prepared to play opposite a singleton unless you have no other good alternative. Here 1NT with Kxx in the unbid suit looks like a great alternative. So could I ask (Justin, kayin, fromage, etc) for the why on choosing 2♥. This is a proper B/I question and the answers will hopefully be useful for many.
The first question to ask is whether partner's 1
♠ promised shape. For me and many others, it would promise at least 4=5 blacks. In BWS, I understand that it promises at least 4=4 blacks, while for diehard up the line bidders, it may be 4=3=3=3.
The less shape is promised by the 1
♠ bid the more one stands to benefit from rebidding the 6 card suit. But even if opener promised shape, there is some chance of a 6-3 fit and a decent shot at a 6-2 fit.
I think we'd all agree that the odds favour playing in hearts anytime we have an 8 or 9 card fit, especially since in notrump the opps will often be able to establish diamonds fairly quickly and, if partner is passing our 1N or 2
♥, the opps will have values and thus entries.
But what about 6-1?
Our hand is not going to take many tricks playing in 1N when partner has a stiff heart. We cannot possibly establish hearts and run them, even if we can preserve the diamond K as our second diamond stopper. So we can contribute at most 2 tricks to the offence, and we have no fillers or length to help establish long suit winners for partner. Playing 1N will probably develop into a bit of a scramble, with both sides searching for that 7th trick.
In hearts, otoh, if the suit breaks reasonably well, we can establish some small hearts as tricks. Alternatively, the black suits may lay in such a way that we can 'elope' with some small trumps by way of ruffing. In addition, if the opps are in a position to run a long suit (it could be diamonds or spades, but unlikely to be clubs if partner has a stiff heart), we can at least try to stop the damage by ruffing and regaining a tempo.
So even if one were of the view that partner probably has a stiff heart, there are still reasons to bid 2
♥.
Make the hand a little stronger, or the hearts weaker, and the arguments change. A stronger hand has more to offer by way of bolstering partner's hand in notrump, and now we might have 7 winners in notrump and be doomed to 6 losers in hearts because of a bad trump break.
The weaker hearts would give rise to the risk that the opps could eventually pull trump or arrange to score their trump separately, because we'd lack the ability to pull them ourselves.
Of course, every now and then partner tables a 4=0=3=6 with which he had to pass 2
♥. Tant pis.
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari