Just to chime in, I've personally witnessed quite a few tanks get harassed in dungeons for not dropping tank stance. It's one of things that kept me away from tanking for a very long time, even though I always wanted to do it. Not that it was my intent to not try and contribute to DPS, but because I find it completely ridiculous for such expectations to exist in a dungeon, and I've already had so many tiring days defending the healer side of this topic. There should be no question that players that carry these high expectations exist in all content, and there are actually quite a few of them from my experience.

I find that tank play is greatly taken for granted in this game. A tank who is holding agro is doing a good job, because when they hold agro it makes things easier for everyone else. DO NOT take that for playing optimally. That is not what I mean. When you get a lousy tank, or your tank dies, we all know how much more difficult this makes the run, if not a full on wipe. That madness is all because nothing is casting a net around all the mob enmity.

Community is already short on tanks, and we're going to chastise them for not dropping tank stance, or IOW, flame them for doing their job? Just doesn't add up. It is quite simple though, if you don't like the way your tank is tanking in a dungeon, just ask to be vote dismissed and hop right back in the queue. It's totally win/win since the tank is a hindrance to your playstyle, and you are a hindrance to their growth.