It's not a Heavensward dungeon, but Wanderer's Palace Hard first boss comes to mind. I started turning Grit off for that fight after securing hate since I kept seeing him take only one or two swings at me before turning around to do some fool thing against my team mates to put him down faster.There are fights where you can let loose and go sword stance or just try to max your dps out as a tank, but those fights are against bosses that stop continuously beating on you and are trying to do special attacks.