You know what annoys me more than bad players??? The "GREAT" players(most of the time i90 or higher) that queue up for drlow and then quit on joining the same old instance. Newbies and bad players have potential to improve - those don't. If I have time to monitor what they are doing I will suggest improvements to newbies and bad players. Some will improve some won't. Nothing I can do that. But I always do it in a polite way and I stick with them(I've had gladiators and marauders in bray nm and in titan nm - along with other classes - and that's fun to explain to people to get their job crystals - but I recall I was similar to that myself at one point). I have seen players improve from the start of the run to the end of it from taking advice on board.

But I must say I had very few bad experiences in dungeons. The first place I tend to notice bad rotations is in primals really.