This was North's thoughts:
Pass pass 1S 2D
X pass 2H pass
?
After my take-out double, partner's bid of 2H could be a forced response holding only 3 hearts. Say 4333 or 5323 with no diamond stop prepared to play in a 4-3 heart fit. So since I have a double diamond stop and 11HCP, the hands may well play better in no trumps if partner has only 3 hearts. Partner should know that I have 4 hearts, so will correct my bid of 2NT if he does indeed have 4 hearts himself. So I will bid 2NT.
Pass pass 1S 2D
X pass 2H pass
2NT pass 3C pass
?
What do I make of this? I have no idea except that it must be showing at least 3 clubs, so just in case partner has only 3 hearts, I will pass.
This was South's thoughts:
Pass pass 1S 2D
X pass 2H pass
2NT pass ?
What do I make of this bid? Partner did not bid 2NT initially, but made a take-out double, which I would expect to show a 4-card heart suit. Had he instead bid 2NT in this position, we have agreed that this bid is natural. Could partner have a 1435 or 1444 distribution with diamond stops, or perhaps 1345 with 11 points and too weak to bid a forcing 3C, or even 2443 with diamond stops? One thing is certain; we don't want to be in 2NT even if partner has only 3 hearts. So the choices appear to be:
a) Bid 3H, hoping that partner does indeed have 4 hearts, but possibly leading partner to believe that I have 5 hearts.
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c) Bid 3C. This should tell partner that I don't like no trumps, having at most a singleton diamond and since I did not bid clubs before hearts, I must be either 5404 or 5413 and I cannot be 3323 (otherwise I would not take out of 2NT)
It looks, therefore like I should bid 3C which partner will pass with 1345 or bid hearts with 1435 or similar. OK I will bid 3C.
Apportion the blame please.