[jeffnc]

Yes and no. Floor people still don't know how to play this, which is sad. When aggro mucks his cards they're mucked (not irretrievably, that's strictly a practical matter, not a technical one.) That means he gives up the pot and doesn't have to show his cards. You never have to show your cards if you don't want to. You can muck. You only have to show your cards if you make a claim to the pot, unless everyone else mucks, in which case they forfeit the pot to the only live hand left, which is you, and you don't need to show your cards to claim the pot if you're the only live hand left.

The only exception to this (and it is an exception) is the "show all hands" rule which can be invoked if you suspect cheating or collusion. But invoking, you are saying you suspect a player of cheating or collusion, and this is how the floor should enforce the rule. The floor should have said "Do you suspect this man of cheating?" When you answer no, then the floor says "His hand is mucked, you receive the pot, next hand."

But, floor people are either
1) clueless
2) want to make extra sure there is no image of possible cheating, so are very willing to expose cards even if most players don't get the rule (they err on the side of exposing cards to keep everything on the up and up.)