SE... please (an honest DRK).

[Valdegarde]

Here's why: seen any PLDs in world first for any tier during HW? How about this tier, see any world first for notable content? See what I mean?

No, because simply being in a world first party isn't the only metric by which a class' performance can be judged. Paladin being behind in Heavensward did not make them unusable, just (vastly) less preferable. Dark Knight being world first in some places doesn't make them on par, and does not disqualify them from being less preferable. There are many factors involved that people love to ignore.

Off the top of my head, Paladin was in the world first clear for A2s. Clearly this means it was fine for the entirety of Heavensward by your logic. If this statement upsets you, consider how it makes Dark Knights who feel their class is less valuable lately. The first reaction is for people to cite the Ultimate clear and completely invalidate any input the actual majority Dark Knight player base has to say.
Is it so hard to believe that Dark Knight could use some improvements and that would increase tank balance?

Continuing that line of flawed argumentation, we have not seen all of the world first teams for the rest of Omega and any other critical fight. With the usage rates as they are (which is also not the end-all metric by which to judge Dark Knight receiving aid), would it be a stretch of the imagination to conclude a Dark Knight composition is less likely?

I'm genuinely curious, why would it be such a bad thing if Dark Knights could get some of their abilities reworked to continue to refine the class, even if such changes don't dramatically alter performance?
Edit: I've been told Paladin was world first for at least A1s, A7s and A9s as well.