Not sure if it's reportable, but if I get something that like that I generally either bite my tongue and move past it the best I can or I'll say something back if it annoys me enough, then move past it after the instance is over. I hate it when dps pull for me too but it's something we generally deal with and get used to just pulling the mobs they did. That and it can be considered griefing if we let them die because we didn't take the mobs off them...which is reportable.