[uva72uva72]

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19 of 22 Souths doubled 3♣ for take-out, which 19 Norths converted to a penalty double, earning the predictable -470. Such conversions should be rare sitting under the pre-empter; in a case like this, where North holds a perfectly fine (♦) suit to bid and no prospect of a single trump trick, it should be out of the question. On this hand, even if South holds another Ace for the take-out double, you're only going to beat 3♣ by one trick. Ironically, one of the 3 Souths who did not double passed over 3♣, and North re-opened !!with a take-out double!! It can't be right to make a penalty-pass and a take-out double of the same bid with the same cards. At lower levels, the robot loves to cue bid in response to t-o doubles when it lacks a major suit; why doesn't it do so here since bidding ♦ is presumably out of the question?

[1eyedjack]

I dunno.

I sympathise, but also I can construct hands for South's double where passing by North is the winning action.

Furthermore, "just" taking 3CX one off is a good result if it is your last chance to go plus.

[iandayre]

Sure hands could be constructed where pass leads to the only plus, but they are strongly against the odds here. One should always assume that a takeout doubler holds a small singleton in the opponent's suit until further clarification. Also, the advancer's hand is good enough that a plus will usually be quite achievable on offense

[ArtK78]

Just another example of the old adage - takeout doubles should be taken out.

I would hope that no human player would pass 3♣x on the North hand. But I am sure that some would. You are almost certainly spotting the declaring side 7 trump tricks with no assurance that you can prevent declarer from getting 2 more. And, if declarer has no additional tricks, your side may be able to make a grand slam.

As it is, your side can only make a vulnerable game and their side makes 3♣x. That is a pretty sizable swing at IMPs, and probably in excess of 65% of a board at matchpoints.

[1eyedjack]

ArtK78, on 2014-July-11, 11:41, said:

As it is, your side can only make a vulnerable game

Yes, fortunately doubler has a 5 card major, and fortunately they break 3-2 so you can accept the force.

[ArtK78]

1eyedjack, on 2014-July-11, 12:34, said:

Yes, fortunately doubler has a 5 card major, and fortunately they break 3-2 so you can accept the force.

Even if you could not make 4♥ or any other game, the result would likely be better than -470.