While I agree, at the same time if you're gonna do a dungeon blind then you're probably gonna die at least once or twice while figuring out the mechanics, which is especially a pain if you're playing healer since it's 99% Picromancers and Vipers as party members, meaning that you ain't getting rezzed.
Plus there's bosses like 2nd dungeon 2nd boss where you can easily get killed because instead of stacking on you, morons run away with the donut marker and clip you, or they stand on you with puddle markers.
Either way, I'd like to think it's not too unreasonable to ask a tank to just wipe instead of making us watch them solo the boss from 70% to 0. I want to actually play the game, not play spectator mode to someone's ego.