For the sixth straight month, I am using a deal my team played in the 2023 Senior Team Trials:

Vul:Both Dlr: East	87 Q107 Q72 AJ972
KJ653 K8 1063 K64		Q104 5432 54 Q1053
	A92 AJ96 AKJ98 8

South opened 1 and West overcalled 1. North raised to 2 and East raised to 2. South now introduced the hearts (3). This shows a strong hand with game interest (and is ostensibly natural). North raised to 4, a 4-3 ("Moysian") fit. As you can see, 3NT fails (spade lead and the K is wrong). Meanwhile, 4 was a great contract.

West led a spade and declarer reflexively ducked (to maintain control/communication) East's queen. East, a many-time world champion now found a brilliant defense. He switched to a low club. West's king drove out the ace. Now, when declarer lost the heart finesse, another club forced declarer to ruff. Declarer eventually lost control and finished down 2.

South's "autopilot" duck at trick one was fatal. This is an easy contract to make as long as hearts are no worse than 4-2.

Do you see it? Simply win the A and play a low heart. If the defense takes the king, win any return and draw trump. There are 10 easy tricks (3 hearts, 5 diamonds and 2 aces). If the defense ducks the K, simply win and duck another heart in both hands. If they duck that (not on this deal, of course), lay down the A and run diamonds--again 10 easy tricks. Well bid, poorly played. The other table played in a diamond partscore, making 11 tricks.