You can't play the classes that share similar jobs the same I would have thought that was obvious. Take the tanks for example the war generates a lot of agro just by opening with tomahawk and two overpower and the mob is literally yours all day long because every move he does is hate a few steel cyclones some combos another overpower just for good measure and you can spend your time pulling them through the dungeon to the next mob. A pld has lots of def but you have to constantly keep on top of the aggro list he can hold the hate just fine if managed properly but the mobs will fall off if you're not careful or you don't have flight or fight up for the later dungeons.