Executive summary of my quasi-rant: if you are called and your opponent doesn't instantly and obviously reveal out of turn, failing to reveal your hand promptly is an annoying breach of etiquette.
Surreal Lunch Poker (hereafter SLP) used to do tournament-style all ins: by house rule, both players would show their hands, and the hand would be dealt out. Now, we have gravitated towards true cash-game style: in an all-in situation, neither player is required to reveal his hand until the river, at which point, the player who was called is obligated to show his hand first. Then, the caller may opt to show a better hand to take the pot, or just muck. (Or show a worse hand, of course.)
Now, it's the responsibility of the caller to force the called to reveal by leaving their hand face down until the called player shows. Many players, myself included, are aware of frequent opportunities to avoid showing their hand when their all in is called, because many players habitually flip their hand up tournament style after they make the call. The called player sees that they are beat, and opts to muck.
Martin pulled this on at least two people today: TJ called Martin's all in, showed his hand, the board was dealt out, and Martin mucked. It happened again against Dave, even as I was telling him, "You called Martin, make him show his hand."
We discuss this aspect of our game a bit, and Martin said something along these lines: "If you call someone's all in and you have a really strong hand, though, you should show right away; it's bad etiquette not to."
As someone continually frustrated by having to ask Martin to show me his hand when I've called his all in, I vehemently disagreed. I went as far as to say that Martin's tactic of never voluntarily revealing his hand when he moves all in and is called is, in fact, a far worse breach of etiquette. (To his credit and to the amusement of the table, Martin agreed.)
I want to take it a step further and say that:
1) Forcing someone you have called to show his hand when you are holding the stone-cold, unchoppable nuts is not in any way a breach of etiquette. Poker is a game of information, and you should absolutely get every shred of information that you paid for.
2) When you are called, refusing to show your hand until you are verbally requested to do so is a breach of etiquette, and is in fact, borderline angle shooting when done habitually in an effort to avoid showing hands.
I'm talking to you, sushicowboy.
You are the king of reverse slowrolling...even though you know you have been called and you know it is your obligation to reveal your hand, you sit there at the river and wait, hoping to induce your opponent to reveal first. Many of your opponents at SLP and WNP eventually oblige you in this spot because they don't have these fine-point rules down pat, and figure they must have to show.
Or, my other "favorite:" when they don't reveal on the river, you slooooowly staaaaaaaart to tuuuuuuuuuurn your haaaaaaaaaand ooooooooooover....your opponent sees you doing this, turns their hand over at normal human speed, and you muck before revealing yours.
So, since it came up today, I'm officially calling you out on it, Martin. It's BS. Stop playing head games at the river, trying to induce your opponents into showing first when you were called. You were called. Show. Your. Damn. Hand. It's especially frustrating to watch you attempt it against players like Nick, Joe, myself, and others, who are only going to let you get away with that crap in our very weakest, distracted moments.
I don't blame you for the hands like the ones against TJ and Dave today, they both revealed their hands while the final card was still being dealt, and I would happily muck my losing hand in that situation as well. However, if someone calls my all in, it gets to the river, and they have made no move to show me their hand, I show mine without hesitation.
Because that's good etiquette.