Scoring: IMP
When this hand was played in a tourney, at a few tables South was declarer in 3NT after East had bid hearts, and West duly led the ♥2
East won with the ace and returned the 4, but South goes in with the king, seemingly blocking the suit.
At both tables where this defence was found, declarer went on to make his contract. Did the defenders misdefend or can declarer always make? (I know the answer, by the way, which is in hidden text below).
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