What in the world is happening in here? How could something so simple get conflated into this shitstorm.
Blood price works by DRKs getting hit. DRKs don't get hit if all the mobs are stunned. This makes it hard for us to spam either Unleash or Abyssal Drain as both of these AoE skills consumes a lot of mana.
Yes WHM Holy is greater than both Abyssal Drain and Unleash in raw potency, but I think what most DRKs are asking for is that, if you see Blood Price pop up on our status bar to please not use Holy during its duration. You can use anything else in your arsenal (and there's WHMs in here thinking that DRKs want them to stop DPSing for 15s altogether, I'm not sure if they're trolling, or if the only damage spell they legitimately put in their skill bar is Holy cos screw Stone III, Assize and Aero am I right?)
That being said being considerate also goes both ways. As a DRK I don't use Blood Price at the start of every pull (cos you'd be sitting on full mana and the massive MP regen you get from Blood Price would be wasted anyway). I pop it after I go down to about half my mana pool (about 4 GCDs in). If I see that the WHM has started Holy spamming during the beginning of the pull (which is usually when most DPSing WHMs start their Holy spam), I'll wait till the WHM finishes and then pop Blood Price after.
I expect the same courtesy be reciprocated if you see DRKs pop Blood Price. If you see Blood Price on and go ahead with Holy spamming even when you observe that the DRK is getting low on mana and/or is struggling to keep aggro from the DPS then you're being a major dick to them. We don't need Holy to clear bloody Expert Roulette (where this conversation is even relevant) - you can chuck your keyboard down the stairs and still clear Expert Roulette in reasonable time. But you do need the DRK to be able to hold aggro on large pulls and not be MP starved half the time otherwise the run gets messier than it should.
Surprisingly, most of my Healer friends are WHM and they have no problem with the system we have currently of me looking out to see if they have Holy spam prepped at the start of the wave and if they don't, holding Holy off until my Blood Price is close to dropping off. I personally fail to see what the problem is unless the DRK is popping Blood Price at the beginning of every pull (therefore not allowing the WHM to even get a chance of casting Holy) or if the WHM sees/doesn't see Blood Price and spams Holy and wastes half of Blood Price's duration.