It affects badly other players? Yes. But that's not trolling. You don't see it clearly in that case, but you will in this other case: if one player its very bad (Very very bad) shoud I be able to report him? He might be afecting players badly, and be very annoying. But no one (or almost no one) thinks that shoud be reported. Is the same with that. They are not doing that to troll, it's just that 3º boss, for a really amazing bad desing, have no purpose for them.

Anyway, a suggestion that might work for people having troubles with this: Stay a bit in the dungeon. There's a lot of lazy guys like me that will join 2/3 dungeons because I don't care about mith (And if I cared I woud use pf to get them). Of course it will depend on your datacenter, but on mine I don't think anyone have to wait more than 5 minutes, even for healers or tanks, once in a 2/3 dungeons. Of course is diferent on a 0/3 or 1/3, but that's not the case we are talking about...