Unless you run in progression raid DKs are fine, and thats something that we keep repeating but ppl fail to notice. Noone says that they will be "less valuable" instead its like Chaos said, you just have to work harder to get similar results as, lets say prot paladin.
Its just like Luftdot said, new blood rotation feels simply to much cut down and it feels harder to set up spells than it used to be, at least it was for me too. Im not pro tank, but im tanking farm runs on SoO10HC, im overgeared so thats not that much hard, but still i have general feel and i know how to play blood. New blood simply feels.. so much... slow.. and i mean SLOW.. you just sit on autoattacks, burning your runes on BB and DS, while burning RP via Death Coil or Breath if youre speced into it, It really feels awkward compared to other tanks that are not so much resource dependant like Monks or warriors who always have something to do, nothing more.
I run yesterday on this
Simulationcraft Raid T17N - 9.24.2014 while browsing Enhance shaman's forum on totemspot so this might help a bit. Take note that this is generalized simcraft of CURRENT BETA patch, it prolly means nothing so dont take it seriously at all, but i doubt that blood will change much mechanically so im just posting this cause it looks like bloods selfhealing is insane and you might draw some info from it. Its enough just to look at Wait time and you will know what are we talking about, its still BETA sim, but still it DOES feel like that.
Chaos, as for Death Grip.. iwe been spamming for quite a long time something similar, it was more like DG works normally, but when we cant pull boss mobs to us we should be able to pull our selfs forward to boss, similar to charge, yet different in a DK way. Also, something like that could be implemented as warriors "intervene" where you could DG jump-intervene to a player. But yet again.. that would be to much mobility for one son of a lich, the lich who chases you trough whole dungeon and you manage to escape him quite easily. I think that Devs should think out of the box and move a bit from strict "son of a lich" design and give us some mobility, otherwise we migh end up as slow moving glaciars >___>
Im not asking for something like roll or charge, but simple reduced CD on Deaths Advance and bigger movement boost for shorter duration could do a trick like.. 45% boost for 3sec on 20sec CD.