lamford, on 2019-October-23, 09:40, said:
Maybe he has read Woolsey's article many years ago that the worst leads are the "three-apart" ATxx K9xx and Q8xx. He did have the last of these in fact, and East will shift to a heart if you play a diamond at trick two, when you cannot make it. However, if you play four rounds of clubs first, West is triple squeezed and it is a "clear and obvious error" not to do so.
Not exactly. Playing clubs first wins on that layout but loses on a lot of others. For example, let's say West has this hand:
Qxxx
K9x
KTx
xxx
If you play four rounds of clubs, E-W pitch hearts. Now you lead a diamond up. East wins his A and returns a spade to West's Q and dummy's A. Now what? You can't lead a diamond from the board, or else the opponents will get three diamonds and two spades. You can't lead a H to the Ace, or else the opponents will get two diamonds, a heart, and two spades. You are dead. On the other hand, if you lead a diamond up at trick 2, the contract is gin. If the opponents continue spades, they get 2 s and 2 d. If the opponents switch to hearts, they get 2 h and 2 d. You get 9 before they can get a fifth.
Quite honestly, I think a hand like the one I posited is a lot more likely than the actual hand, because with the actual hand, it is very possible that West would have led H rather than dummy's spade suit (sort of a restricted choice variant).
Cheers,
Mike