DRK doesn't need simplification, what it needs is mechanics that are a net gain or a net loss, instead of things that simply break even. The job is PACKED with choices to make and priorities to manage, but no matter what you choose or prioritize, it barely effects your performance. Because of this, there's barely any incentive to optimize the job, because you're rewarded extremely poorly.
The reason Bloodspiller's tooltip is worded the way it is, I assume, is because unlike Inner Beast, it is not locked behind Grit. Also because of its buff, it no longer simply ignores the penalty, as Bloodspiller is now 400 potency out of Grit, so its baseline Grit potency would have to be 500 and the DA+Grit would have to be 675. The way they have it now they can adjust the potencies individually, whereas with something like Inner Beast they cannot. I'm not saying I'm a fan of this though, as I would rather they simply make up their minds and have Bloodspiller be a defined DPS gain regardless of how we build the Blood to use it.
Currently we have a ton of mana dumps and they all net almost the exact same potency increase with the sole exception being Carve and Spit. The reason for this is because they backed themselves into a corner by removing Delirium and making the changes to Darkside and Blood Weapon for their mana drain/recovery respectively, meaning that if we go through our rotation and only ever Dark Arts Souleater or Bloodspiller we will overflow constantly. So they made Syphon DA-able. Now, why they did this as opposed to simply keeping DP where it was (which would have achieved the same purpose more or less) escapes me. And it really just drives home the thing that a lot of DRK's have been complaining about since day 1 of SB: They didn't buff the job or improve it at ALL with the release of 4.0, they just rearranged a bunch of crap.
If they want to make these DA potencies the same, then the abilities need additional DA effects (Bloodspiller could have a DoT, Souleater could see a greatly increased self-healing effect, Syphon could lower the cooldown on one of our oGCDs or perhaps simply restore more mana, etc.). These abilities need to have some form of parity but they also need a reason to DA one over the other so that the job can have something resembling satisfaction for optimiztation.
On a side note, I'd like to point out that in HW, SE released a fairly substantial job adjustment patch after the launch of Gordias savage but before 3.1, in August of that year: http://na.finalfantasyxiv.com/lodest...7aff5b99d9fb32 ...so if we continue to provide this level of feedback we may see some of these fixes we're suggesting this month.