Is this really a good slam? Wouldn't a diamond lead through the K defeat it, possible 2 due to a diamond ruff? 1♣ - 1♥ 1♠ - 2♦ (1) 3♣ (2) - 3♥ (3) 4♣ (4) - 4♠ (5) 5♥ (6) - 6NT (7) (1) 4th suit game forcing (2) Confirms good 5-card club suit (3) Confirms good 5-card heart suit (4) Confirms slam interest, since it bypasses 3NT (5) Spade stopper (6) Heart King. (7) Responder sees 6 heart tricks, 3 club tricks, 1 spade trick, and since opener must have 18 points or so for slam try he must have something in spades.