When should the dealer muck folded hands at showdown?

[youtalkfunny]

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I believe that a discarded hand should be mucked immediately so that it is irretrievable.

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I hear this a lot.

I do not agree that it is the dealer's function to actively seek out hands to kill. Nor do I believe that he is necessarily slacking if a player is able to retrieve his cards before the dealer is able to kill them.