You can actually still maintain aggro lead without tank stance. It's just harder to do for now. However, if you pull it off, you can still do way better dps. For every combo, you get 50x3 potency from Sword Oath, even if you spam Halone ((150+200+260pot) x 100% mod + 150pot from Sword Oath = 760) combo way more often, it's still better than be in Shield Oath and spam Royal Authority ((150+200+350pot) x 85% mod = 595). And those numbers aren't including autos yet + multipliers from FoF and other buffs/debuffs.
Note: excluding Goring Blade combo because it's still a priority to put it up no matter what.
