It's not just DRK it happens on quite a few tanks. To me its up to the healer not the tank.

If the healer says it's a no go then its a no go.

We had a DRK doing this last night on A4 and he was getting face smashed and our healers got tapped out before the second leg was down. Now you could say it's bad healers but it seemed like bad cd usage on the drk imo.