whereagles, on Nov 8 2006, 02:52 PM, said:
Assuming perfect defense, game needs a spade honor onside and the heart finesse. That's roughly 75% of 50% = 42,5%, or of the "worth bidding" type
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A bit more if you guess a singleton trump honor right.
The only problems with this are:
A) you dont account for a heart or spade lead (admittedly a spade is unlikely). On a heart lead you are in good shape. At MP do you usually make aggressive leads into the strong hand after invitational auctions? I don't. A heart lead from 3 or 4 small is certainly a strong possibility, and is likely without a minor suit sequence on your left.
B ) You assume a bad line in spades. Double finessing is the worst line.
C) You don't need a heart hook if spades come in for 0 losers.
D) You can make it even on a club lead even when you have 2 spade losers if it's Kxx of hearts onside. Now in theory this is a 0 % proposition as you would never pick it up, but lets say you win the club lead and play the heart jack. It gets covered. LHO now gives count showing an odd number! you play a spade to the ace, no honor falls, and you play on hearts. LHO had KJx of spades and xxx of hearts, well played. Or how about this line... you win the club ace and lead a heart to the queen. It holds. You cross to the spade ace and lead a heart. RHO plays the king. You now play a heart to the jack and they ruff but only get 2 spades and 1 club (you pitch the diamond on the spade). Well the problem with this play is that LHO may duck the heart king and also that the only holding youre actually gaining against is RHO holding a stiff spade and the Kx of hearts, not too likely.
These percentage calculations are very flawed. If I'm in a contract needing to pick up xx opp KJx, I do not see that as 50 %. That should be calculated as at least 60 %, perhaps more, yet it never is. Assuming perfect defense is very flawed as well, you don't get it ever. If the opps are defending perfectly you are going to lose so just quit. Good declarers are going to find some lines that are 0 % to find on paper, thats why they're good. This will happen far more often than them going down in a 0 % possibility on paper. It does not cancel out, declarer has the advantage even against equal skill opposition.