Pld Oath's on GCD

[Lyth]

DV also requires a cure, so either the healer has to provide one, or the tank has to waste 3 seconds clemency/curing themselves. The key distinction between these 3 skills that makes SP much better is the fact that it is the only one that can easily be done as an OT (which could be fixed by giving it a bonus if hit from the front, but of all the problems that tank balance has, this is low on the list).

DV shouldn't be used on a whim. You plan its usage in advance, ideally with your healers. There are a lot of heals that will proc it, including AoE heals and shields. It doesn't really matter if you're MT or not. In fact, it's also the only one of the three skills that can be used in the absence of a target.

SP is more readily available (at the cost of dps), but if you need a large amount of mitigation for a single big AoE, DV is unsurpassed.

That is the problem, actually. WAR has a great skillset with a bunch of useful stuff, both for tanking and support. DRK got a copy of PLD's basic skillset with a magic twist, then a bunch of duplicated skills to just increase its own dps. DRK could easily lose 5 skills and gain slightly more potency on its combos to make up for that. Reprisal (procs are a big part of why PLD/DRK have to tank, and DRK already has Delirium for damage reduction), Carve and Spit, Dark Passenger, Abyssal Drain and Plunge (could have gapcloser moved to a DA effect) are pretty much all just used for dps and waste slots. What would go in those slots? I don't know, it would be up to SE to add stuff that would make DRKs feel powerful and useful to a party. PLD could use the same on skills like Cover and Tempered Will (they're too niche) but at least it's on the right path with Clemency and Divine Veil.

DRK's playstyle is designed to be fast paced. Blood Weapon, and the numerous oGCDs that we get are part of what give the job its style. If you want to play something which only requires you to play with half the APM, then there are already jobs that cater to that, like BLM and WAR.