Honestly my current tanking macro makes it almost impossible to pull aggro off my DK:
Castsequence:
IT>PS>Pestilence>BS>DS
I throw a DnD out just after the icy touch (basically use the IT to pull, then drop a DnD, then continue on with the cast sequence). Once the DND is down I can open up wide with my shamans and not pull aggro - especially once pestilence kicks in.
Once the patch comes out and they drop the cost of Unholy Blight to 40 RP I will add the following line above the castsequence:
/castrandom Unholy Blight,
This will drop through if I spam the button and don't have enough runic power for UB, but if I do have enough RP it will use it. I am probably going to modify my cast sequence to use Blood Boil instead of Blood Strike - I haven't really touched the sequence since I made it since it holds aggro 100% for me already.