Should Dark Knight get a Rework?

[Shurrikhan]

Abyssal drain is something you hold until you need healing.

You should still typically be trying to use it as soon as you can in dungeons, as it recharges that much faster. Better to delay Shadow Wall slightly and let yourself get nuked down to what AD won't overheal than to hold AD for until you're on your last legs.

As for AD giving MP, yes. That's the point. It gives MP now, and that's the only thing it has in common with C&S in terms of effects.

And that they are damage CDs. Which is also the only thing in common between every other AoE-ST shared CD/Resource pairing.

Because C&S is there for burst windows of damage that line up every minute, be they major or not. Abyssal Drain is a large AoE skill that provides sustainability.

AD is still a damage CD. Yes, anything with AoE in this game gets downgraded to content doable while wasted beyond belief, but... you should be popping AD under raid buffs, as with any other damage CD. If that means shuffling longer mitigations CDs back/around slightly as not to overheal, so be it, but --like Dark Passenger and Shadowbringer and resource spending in general (including AD spam in the past)-- it should be done under buffs where possible. I know it doesn't feel like that much since it's been so squished to make room for Shadowbringer and the frequency of Flood, but it is likewise a damage CD.

Uh... then I played DRK wrong because I basically only ever used it for healing.

The portion of Unleash to AD, and when to switch from one to the other, was pretty entwined with Grit and thereby Blood Price (which could only be used in Grit during Stormblood). You tended to blow enough Unleash while Grit was still active to cover for using only AD thereafter, aiming to drop Grit with resources still high going into Blood Weapon so that DA-Quietus could refund its own Blood cost. With high enough mob counts you could use that to refund the MP costs of DA-AD (about a third of your MP per cast), but spending more than you needed to on healing would ultimately cause you to exit a non-Delirium BW phase with too little MP to spend the whole remainder of the pull without using single-target skills.

DRK could push WAR's ridiculous Stormblood levels of AoE output at very high target counts off the back of BW-Quietus and AD (part of which included exiting BW phase with still nearly full MP). Using AD over Unleash was absolutely a factor in that, though.

Abyssal Drain is the answer we have for sustainability.

Anything that provides sustain is an answer to a lack of sustain. It does not require removing AD from a free cast on CD and making it again a spammable spender (to the detriment of maximum combined sustain + throughput and/or redundancy with Flood).

You could as easily have Blood or MP spenders grant a portion of damage dealt as healing. Voila; sustain. You could just buff Abyssal Drain and make it more flexible. Voila; sustain. You could make Dark Mind not crap, having it produce further sustain. Again, anything works.

Whether we do or not is kind of irrelevant... WAR doesn't have one on its AoE kit, but it does have Bloodwhetting which does it for them. Abyssal Drain used to be the equivalent: it was our AoE sustain.

Abyssal Drain was originally more equivalent to Clemency and mirrored Grit DA-SE (SE only healed during Grit originally). It was a potency loss (opposite the potency gain of DA-SE) in exchange for target-scaled sustain. Only now is it at all equivalent to Bloodwhetting as free self-healing on a CD.

Carve and Spit was in no way attached to it whatsoever, and there's no good justification for it.

I don't know why you keep focusing on the CnS-AD resource pairing. They're together only because AD's 150p attack felt, to many, more "clunk" than "complexity/freedom" in raids and CnS didn't feel terribly useful in AoEs, so the ShB opener was made slightly less crowded (in preparation for Shadowbringer as an ability) and DRK was made able to go 100% AoE with its spenders in AoE situations. They were never able to be that diverse in practice.

Now, DRK has its "equivalent" to Bloodwhetting's AoE effect (note that its ST effect, too, is similarly comparatively dog****) in/via Abyssal Drain, albeit at a timing more equivalent to any other primary sustain CD (Equil, Aurora, Req-based heals) or core damage CD (Req, FoF, NM, IR); it's just tuned needlessly weak by comparison. That's not an issue of AD being placed on a cooldown or lacking a duration of effect (bursting from critical to full in one oGCD is fine), but simply its tuning (frequency x non-excessive power).

But it being on a 60s cooldown just because it's tied to C&S is too much for what it does on an AoE pull.

It was put on that CD before being attached to C&S. C&S, also, was originally on a shorter cooldown (40 or 45 seconds).

Because there's no need for AD to have a use in single-target content

No need, sure, but it'd still be a better use for its button-space if it did. I'd say the same for Decimate and Orogeny (to be useful in ST), Fell Cleave and Upheaval (to be --differently-- useful in AoE), etc., etc. Else there's no capacity they could cover that wouldn't already be met plentifully through damage fall-off, and those buttons could be used on something more interesting than "Can you count to 3?"

C&S makes sense to be on a minute-long cooldown.

No more or less than Spirit's Within, Upheaval, Danger Zone, Shadowbringer, etc. It's pretty darn arbitrary.
And again, despite it originally being the strongest attack in DRK's arsenal (at least up until 3 targets, at which point DA-DP overtook it), it started with a considerably shorter CD than it has now.

AD makes sense to have a cooldown longer than Bloodwhetting bc of TBN and Oblation, but 1m long isn't it.

*Can't help but notice Equilibrium, Aurora, and Paladin's 3200 potency of self-healing per minute.*

Again, I'd rather see its CD shortened (and, more importantly, made more flexible via a 2nd charge), but... there's nothing inherently wrong with a damage CD, a self-healing CD, or a two-in-one combo like AD (though decent only in AoE) being on a 1-minute CD. There's no reason for Equilibrium to make sense there and Abyssal to inherently not.

DRK merely needs additional sustain (sum of capacity for damage reverted without excess [effective healing] and damage nullified [mitigation]). Given that its mitigation is basically fine and applying sustain increases across the board would therefore might be excessive to its mitigation, that should mostly come from self-healing. But, we can apply that anywhere.

I like the idea of first siphoning a bit of power from DRK's dullest areas into CnS and AD because a 2-charge 40s CD would then provide at least one entirely flexible use per raid cycle (none if using a 60s CD or a single charge), and I feel that DRK currently has a lack of interesting/punctuating events outside of the 2-minute bursts.

For that self-healing, though, anything works. I'd buff AD a bit, especially against its primary target, just because I feel like it currently has a bit too little numeric impact for what its visuals entail. Beyond that, though? MP spenders and Blood spenders are both more flexible and iconic ways to get at that self-healing that would happen also to (A) not require Abyssal Drain be tuned down in becoming spammable / "at-will" and (B) encourage DRK towards a bit more action/complexity that'd fall outside of the 2-minute bursts. Compensate that healing for some inevitable waste due to burst window optimization, and you're good.