DRK vs. WAR: how do they compare?

[Oizen]

What do you use them for in p5 or p6?
This seems to be more a 2 minute raid design problem than anything.

Also how do you rationalise the existence of dark mind?

P5, you can use an invul to solo the spawn of the add, allowing the OT to act as a fill if exactly 1 person got clipped from Devour.
P6, You can use Invuls on Chelic Synergy to minimize the ammount of bleed your healers have to deal with, if you don't see the value in that I dont know what else to say here.

Invuls aren't worthless this tier, they're just not the insane centralizing force they were in asphodelos.

Also how do you rationalise the existence of dark mind?

Dont know what you expect me to say here, the real answer is that DRK has no longer design philosophy and is just a random assortment of buttons that ended up being more than the sum of its parts. Some of it is leftover from the original design intent that DRK was the magic tank, back when PLD wasn't allowed to block magic, Square Enix chose during the mass removal of DRK skills to keep Dark Mind.

Dark Knight is the only Tank that doesn't get an early version of its mitigation.
It doesn't get Raw Intuition, Sheltron, or Heart of Stone, or Camoflauge. There is no Proto TBN (anymore anyway, Blood Price was kinda close)
They picked Dark Mind. Its honestly near worthless at the level you get it, and then becomes stupidly good once you get to raid content.

Then for whatever reason, they introduced Oblation which basically has all the same upsides of Dark Mind being short CD raw mit, giving DRK yet another button to press.

So while the rest of the tanks get skills with 50 different "Additional Effect" texts. DRK gets another raw mitigation skill that isn't all that impressive on its own, but can be paired with everything else to get an end result better than those other Tank's Super Mitigation skills. TBN also plays into this a bit, as shield HP pairs really well with mitigations.

An Optimist would say this was SE's intent, for DRK's skills to be a sum larger than its parts. I think its more of an accident that just was an inevitability of DRK getting so many buttons and never giving upgrades to them, rather than new skills.