I feel DRK should be the tank that specializes in debuffs on their offensive abilities so that way they are not super squishy outside of Grit, but shouldn't neglect main defensive cooldowns, but that design would require Dark Arts to be reworked completely for DRK to be that kind of tank... which obviously the devs aren't going to attempt to fix DRK until maybe 5.0 is being prepared... but with recent patch notes I'm not keeping my hopes up for DRK getting fixed... they really screwed up DRK balance and all we can do is wait for DRK to be good at doing something that isn't AoE tanking which it also sucks at right now due to Blood Price MP regen nerf...