Dark Knight Changes - Suggestion.

[Shurrikhan]

No where do you see that this fits the description of what effective HP is. Effective HP is the amount of damage you can take before you hit 0. Mitigation is always referred to as a "reduction" of something, in the case of FFXIV, damage received.

If I take 40% less damage, my maximum eHP is now my max HP divided by (1-0.4), and any HP consumed during that time constitutes 1/(1-0.4)x the effective damage consumed. It increases current and maximum HP.

If I increase my current and maximum HP by 20%, as a barrier or through the likes of Thrill of Battle, my current and maximum eHP are both increased by 20% of my max HP.

If I heal for 1000 potency and another 1000 over n seconds, I have increased only my current eHP, not maximum eHP, because I am still capped by the same maximum as before and have not increased the value per health point of what I have/had.

they say "comparison is beginning of despair". it's truth it seems. I have all tanks leveled and play them all and while i think DRK is coolest visually, except running animation, the class is wreck. DRK have Darkside, but so does WAR. But WAR have it as passive on 1,2,3 and in AoE combo. You don't even need to think about it. DRK must spend MP to maintain it. And DRK MP regen sucks. We only have delirium which is quite bad. PLD also use MP but have insane regen on 1,2,3 and passive that cuts spell cost by half, so PLD have virtually infnite MP. Now DRK have lot of oGCD, sure it has. So does GNB but GNB oGCD's don't share CDs with each other. Let's not forget DRK crappy sustain. When you look at class objectively it's a wreck. DRK atm is discounted version of every other tanks

How does any of what you mention here make DRK "objectively... a wreck"? Darkside is virtually nonexistent, yes, but DRK does more with MP than PLD does with its MP and Oath combined or WAR does with its Surging Tempest. PLD has "insane MP regen" because it doesn't matter; its offensive spells aren't worth using outside of its 1-minute CD anyways, so you could remove MP costs from all but Clemency, tone down the regen proportionately, and nothing would change and no one would be the wiser.