Total damage has to be the worst indication of how much damage is actually mitigated ACT has a parry chance for a reason, Total damage doesnt take into account what if the boss crits what if you didnt use a cooldown when you should of, theres alot of variables in total damage, say 503 parry gives you a 20% chance to parry and 603 gives you a 25% chance that becomes you have a 25% chance to parry or 25% chance to block with onion shield thats alot of mitigation