Just because a mage can pop their cooldowns and burn all their mana in the 30-45 seconds a boss lives in a heroic and do 5k dps doesn't mean that it practical or possible for all classes. If you've got a full group of fresh 80's even your mage couldn't pull that off because you'd run out of mana so quickly and your mirror image etc wouldn't be up the whole time.Originally Posted by SilkforCalde
I'd also say that depending on the tank and the dps it can be hard to out dps the tank on the trash pulls. A warrior or pally with heavy block/str gear can do a lot of damage on ae pulls with just the damage shield and not all classes have strong ae against small groups. Sure a warrior or pally cleaving the group is going to go crazy but many classes don't do well on AE with only 3 or 4 mobs.
If you've got a group full of 300dps people, sure, I understand bailing. If your doing 5k dps as the tank and the 3 dps are doing 4k dps there is no reason to drop the group. You are going to be killing stuff quickly and easily.