But...Shield Oath doesn't give any HP while Defiance does? I assume we're talking about Shield Oath and Defiance because Sword Oath isn't really a tank stance
The way you're wording this is misleading. You're saying it like Rampart results in less mitigation than IB, when actually the PLD, with Shield Oath and Rampart, mitigates 36% of damage. The PLD ends up taking less damage which is what you should be looking at here, not just comparing the individual skills percent reduction.The differences: IB does damage and has a self heal, but the big one is that they actually don't mitigate the same amount because of ShO being a base % damage reduction which means Rampart actually ends up being a 16% damage reduction while IB is still 20%.
Again, the way you're wording this casts PLD in a pretty negative light.Sentinel and Vengeance. Sentinel with the trait says it does 40% damage reduction which actually results in a 32% damage reduction and lasts for 10 seconds and is on a CD timer of 180s. Vengeance does 30% damage reduction, does damage on being hit by physical attacks, lasts for 15s and has a 120s CD timer. So they have almost the same % damage reduction, but Vengeance does damage, lasts longer and can be used more often.
It's not fair that you're not counting Shield Oath's mitigation in that percentage, because Shield Oath + Sentinel reduces 52% of damage, which is much higher than Vengeance's 30%. Because, again, you can't just compare the two skills and say "Shield Oath makes this mitigate less" and then not actually tell them how much Shield Oath and Sentinel mitigates.
If you're going to point out that you can only block physical damage, you need to point out that Foresight, which only increases physical defense, would be equally useless.Bulwark and Foresight. This one is a bit harder to measure because of block. Bulwark can give greater burst damage reduction, but block only effects physical damage and it has a shorter duration and longer cool down. Foresight may do less reduction but it lasts longer and can be used more often. The difficult to compare elements are that block could potentially block a really nasty attack or hit, but then on the other hand since block only effects physical damage its effectiveness in magic heavy fights is greatly reduced.
The point is, you can't really say "Because of Shield Oath's mitigation, X skill reduces less damage resulting in Y reduction from X skill" and then not include Shield Oath's mitigation in that. It's not really fair to the class, because Shield Oath is kinda PLD's thing, and with it, it always results in a higher mitigation percentage than any of WAR's stuff.