Ah, I wanted to create exactly the same thread for some time now. We are doing the same strategy with 3 people and we all have 4.5k or more hp (crafted rings and stuff), but the problem is that sometimes fireball will dmg person for ~4k (in group of 3), which is intended and sometimes for ~6k (again, in group of 3), which is insta-kill. Is it that we are very-very unlucky or there is something we are doing wrong?

P.S. All of our static members have 80% or more ilvl 90 gear and we still (rarely) fail to kill 3 stacks conflags (not telling you about 4 stack conflags). How are you doing it?