DRK feels weak

[Ryaduera]

I'll requote myself:

"Mitigation = Incoming damage reduction
Mitigation =/= Self-Sustain"

TBN actually soaks damage before the rest of the damage applies to your HP. Temporarily changing your maximum HP doesn't "mitigate" or "reduce" the incoming damage inflicted to your HP.

Mitigation is literally how much effective HP you have. Shields, damage reduction, and raw HP values are all factors. If you have 80000 hp and you use Ramparts your eHP becomes 96000. If you use TBN it becomes 100000 eHP. If you use TBN with Ramparts your eHP is 120000. If you use Thrill of Battle your eHP is 96000. If you use Thrill with Ramparts you have 115200 eHP. If you then heal after taking damage, your eHP increases by the heal value multiplied by the mitigation value, so if you heal for 3000 (which WAR does several times (per target in the case of dungeons) over the duration of a single cooldown) then your eHP increases by 3600 after the heal has taken effect. The only time TBN is better is when damage bypasses your maximum eHP. This scenario does not exist outside of tools every tank already has because the balance team will never make a single job absolutely necessary for any content because that creates imbalance. Over a longer duration, every other tank has a much greater eHP value even after diminishing returns of percentage based mitigations are taken into consideration. The best mitigation is a combination of HP/Shield values (and yes they are interchangable because in terms of damage calculations they are exactly the same) and outright damage reduction since that pairing does not suffer diminishing returns, so TBN isn't technically bad, what is bad is the lack in actual percentage decreases compared to every other tank with WAR technically being close (still greater than DRK though) but at least WAR can bring themselves to full HP the instant they drop, meaning in the duration of a fight, they have far much eHP to burn through. Nobody thinks TBN is bad, but we do think it doesn't deserve to take up such a colossal amount of our defensive skill budget. A heal over time or actual damage reduction on shield break would fix every issue.

Healing is a reactive form of mitigation. This is why drain tanks exist in several games.

[EDIT] PLD also has less active uses of damage reduction in terms of percentage values but having a passive shield to RNG block damage makes the math significantly harder to work out unless an actual block rate percentage were presented to us, instead we can only extrapolate and infer from what we see, but to my knowledge I don't think anyone actually has charted out block rates, so it's pretty hard to tell how much eHP a PLD has, but it's definitely more than DRK. PLD healing is deeply flawed in my opinion since it is tied to a burst window, but it receives less complaints because at least the job is coherent.