thandrews

I should have been more specific - there is no apparent double dummy difference between these two hands in terms of expected tricks. I can't explain why this is true, except from data. It's possible that the double dummy trick values don't represent single dummy expectations. My explanation - that experts are right about what to do with this hand, but wrong about why - is really merely a hypothesis, not a proven fact.

I would also say "refutes" is a bit strong. What works double-dummy is not what works single-dummy. I bought the leads book - it's not often I get mentioned in a book - but was disappointed somewhat in the methodology. Been meaning to write up a longer analysis, but I haven't gotten around to it. As one of the first people to do serious double-dummy analysis, i'm always careful to avoid making blanket statements about expert practices. Sometimes, I think expert practice is right, but not necessarily for the reasons that the experts think they are right. For example, there is apparently no different in play strength of the two hands ♠T8642 ♥AK4 ♦A83 ♣95 and ♠AK642 ♥AT8 ♦843 ♣95. This is counter to the standard expert view. But the first hand has a drawback. When you open 1♠ with this hand, partner will generally over-value the wrong hands and undervalue the right hands. For example, he will over-value ♠Q53 and undervalue a stiff spade. This makes the first hand a bad opening hand because, although it has the same playing strength, partner's re-evaluation of his hand's worth is going to be wrong. So expert practice to view the second hand as a "better hand" for opening can be correct, even if the expert belief that honors in long suits are stronger is (possibly) wrong. I've always taken the view that if my research contradicts expert practice, I need to look deeper, not jump to any conclusions. But then, I'm a mathematician more than a researcher, and I see my research more as puzzle. In the opening lead research, the big problem is that, if you choose the double dummy best lead, partner can't take any inferences from your lead. For example, if you find a perfect lead of the jack from AJ32, the only way for partner to cooperate is for partner to have a double-dummy analysis, too, and imagine a bunch of hands where you'd make this lead, and then pick the defensive line which covers the most possibilities. That's a tricky proposition. This is why every other book about leads emphasizes the *information* in the lead for partner. The idea of information is exactly what you lose when you use double dummy analysis, and bridge is primarily about information.