If everyone is playing double-dummy, automatic plays become wrong plays and strange plays become correct. To imagine every layout of the spot cards, and to go to a fourth dimension, is to transcend ordinary analysis and play like the gods. The west player on the following hand has an interesting problem when clubs are led. (He gets off to the best lead, a trump, and once again when in with the spade King, gets off to a second trump, the best for his side.) His moment of truth arrives when the four of clubs is led from hand. (This hand is a strange echo of the last post "A difficult 8-card ending", once again the club suit is 4-3 West East) It seems automatic to split from Q, J, T, but if he does, he gets to hold the lead, since his partner cannot overtake, Now, if he continues a high club, I win in hand, and use the two dummy entries (trump and Jack of spades) to ruff a club small, establishing the King, and enjoying it for a diamond discard. If instead, West tries a small club,i duck to East's 9, fly Ace on East's diamond return, cross in spades, ruff a small club, setting up King, and cross to trump Ace to take my diamond pitch.
Thus, West's correct play is to time the first round of the club suit (tempo is important!) by not splitting Q,J,T, letting his partner win the 9 which he has to hope he has!! Now East's Diamond return is in time!
In practice I won 7 IMP as west fell from grace and even spared me the hard work, returning a diamond into the teeth of my tenace