This is a very good slam. Besides one of 2 3-3 breaks (which is well over 50 %) you have extra chances of finding RHO with Tx/Jx of hearts on a non club lead (losing now to JTx of hearts, but this is a definite increase in percentage) or stiff T/stiff J of hearts on a non club lead. You may even get the jack of hearts lead from JT8x(x). You also have some remote squeeze chances on a non club lead (remote, but again adding to your percentage). And even though 5-1 spades set you when hearts are 3-3, you have some chances if there are 5 onside and a stiff honor offside (considering hearts are splitting). Considering a slam needs to only be 50.01 % to bid profitably, I'd say I'd be thrilled to get to this one.

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