Posted 2010-March-26, 12:30
There is an advantage to playing the diamond at trick three.
If the finesse fails and a heart comes back, you have four diamonds, two clubs, and two hearts. Down one. But if you play a club to the jack and then a spade, and a heart comes back... say you now cash the club and take the diamond hook. If it's off, you have lost a spade and a diamond and now the opponents can cash three hearts and a club for down two. So you have three lines:
(1) Win lead, club ace, diamond hook.
(2) Win lead, club ace, club to jack, spade king. Win return, cash club, diamond hook.
(3) Win lead, club ace, club to jack, diamond to ten.
Line 1 and line 2 are equal when the diamond hook wins (both make 11 tricks). But line 1 is better when the diamond hook is losing (down one instead of down two). Thus line 1 is superior to line 2. The only exception is if the club queen was some kind of tricky play from Qx, in which case line 2 discovers this fact early enough to run the clubs. But such a falsecard is ridiculous at any level of play, so we can discount the possibility.
Line 3 is better when the diamond hook loses, as it guarantees nine tricks regardless.
So the question is, which has heavier weight: (X) the very slightly better than 50/50 odds on the diamond finesse due to the club break and RHO having more known cards (Y) the possibility that some people are not playing 3NT, or are playing 3NT from the opposite side, or played the club suit by leading low towards the jack at trick two.
(X) suggests line 1 is slightly better than even odds, whereas (Y) suggests line 3 because you always beat these other pairs by making the hand. My belief is that (Y) is large enough to make line 3 superior (due to gross incompetence in a weak field, due to people opening 1NT with some range other than 15-17 on the north cards in a strong field).
Adam W. Meyerson
a.k.a. Appeal Without Merit