MrAce, on 2014-November-26, 18:37, said:
I think it is pretty odd that you are thinking about 3 or 4 NT, and somehow it is going down, and you are trying to gain by doubling them with the hope that this hand plays 3-4 NT and everyone goes down, probably more down than 5♣ while you take them down doubled. Ignoring much more probable scenarios. I can bet my paycheck (which won't make you rich but still) the probability of 2 NT opener showing up with a club honor, or probability of them already being in a wrong slam, or probability of them making slam after your double, or your double adding very little to our score...sum of all these outnumbers the probability of them going down in 3 NT, which by the way has to take under tricks as equal or worse than 6♣ in order to justify the double.
This is not a normal auction. But what does this add to your argument anyway?
In a matchpoint event, wouldn't you expect that good portion of the field will play some number of NT? We have no real idea about what our RHO holds - I mean, what kind of hand passes and then suddenly jumps to slam? A flawed preempt? Ok, but this means different things to different people, and we can both choose hands to prove our point and what this shows.
Im really not convinced that 3 or 4N is making, and this is what is the key to my argument.
If the clubs are on our right, then its a very good chance that NY makes, even on power. If one club honor is on our left, 3N could still go down - take the dreaded Qx opp ATxxxxx that everyone seems so worried about. Clearly declarer isn't burning entries to lead toward the Q, so may just go down on completely normal play. If we are pushing the board with tables defending NT, we pick up one matchpoint against every table that isn't doubling. I'm really not disagreeing that there's a club honor on our left, but I wpuld suggest it will frequently be a doubleton. I do take issue with a lot of constructions where it affects declarer's play.
Again, when we double, we are turning a pretty bad board into a zero when its wrong. If everyone else defends 3N and it makes, it makes little difference if we double or not - we are getting a top or a bottom defending on the success of the slam. Yes, doubling makes it slightly more likely that they will make slam, and maybe I am underestimating this, or maybe you have a selective memory about when it was wrong. The important comparisons are when other tables are beating 3N, and we can increase the penalty by doubling.