The problem with it is that then the tank has to chase down the mobs you pulled, wasting gcds trying to hit them while failing to compensate for the positional lag as they chase you and not the tank. Aside from that if you can manage threat better than the tank while keeping the party alive, go for it I guess.

I generally wall-to-wall regardless of what the party thinks, and if we die, well then that's their fault for not keeping up on healing and dps -- unless I have under geared/leveled noobs, I tend to back off a little then.