I don't mind PUG groups, I don't set rules, but if we were to wipe on a large trash pull or a boss with a lot of adds, and they start asking what happened, I usually tell them what happened, that they didn't aggro the adds that were attacking me. They usually say OK and will watch for the adds next time or I'll call out that the adds popped. I generally try to have the camera view out far enough to see everything that is going on so I know who to heal first. And if they don't listen then they will start saying that I'm not healing enough (even though I just got praise from them for a previous boss uber healing), and rage quit. That's just my thoughts on this topic.