if your main is the tank, then you've got a good chance for your team to survive pvp encounters better. just keep your healer huddled in the group so that they're not easy to target and spam away on heals while your others dps the tank's targets down much like pve and instances really. just don't spread out your slaves in the middle of a fight and if possible, once you encounter someone engage and try to back up a bit into the groupm