This deal is from the finals of the 2022 U.S.A. Team Trials. At both tables South opened 1. You'd think North would start with Jacoby 2NT and reach 6 or 7 spades. At both tables, North produced a highly artificial auction. One table landed in 6 which was no problem. At the other table, South reached 7 with no opposing biding (vulnerable, West eschewed a 3 preempt). The J was led and declarer tried dummy's queen and ruffed East's king. Since only 4-0 spades with East can be picked up successfully, declarer started correctly with a spade to the ace.
Now what? He continued to draw trump, West throwing diamonds on the second and third round. Declarer could throw a club on the A, so the only issue was how to manage the hearts. With West short in spades, the odds favored West to hold longer hearts, thus the Q. Accordingly, declarer laid down the K (in case East had a singleton queen) and then ran the J, down one.
After drawing trump, declarer could have played three rounds of clubs (K, A, throw a club on the A and ruff a club). He'd discover that East started with 8 black cards and West with only 3. Then, he's surely get hearts wrong.
We can see from our catbird seat that had declarer played on diamonds early, he would have discovered the 8-2 break. That would totally change the odds on the Q and declarer would have played East for it. But, for several reasons, it isn't clear that ruffing a diamond at trick three is the right play. Even if it is, who can figure out down to the last percentage point the right play at the table?
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