Deathstrike - is this a joke?

Please tell me that you do not seriously intend for DKs to be able to spam an attack that hits for 11k and heals them for 18k. I know that this honestly has to be a joke and you must seriously be working on a hotfix as I type this but I wanted to confirm.

If you honestly think this is balanced please feel free to let me know that as well, I will then know that the inmates are running the insane asylum and it's time to move on to something else.