kk well I found this out during naxx
I'm a full unholy spec dk and the other one is a frost/unholy dw spec and well what we discovered is that if
1 DK gets 3/3 crypt fever but doesn't grab ebon plague
and the 2nd DK gets ebon plague
crypt fever AND Ebon Plaguebringer stack
idk if its working intended or not tho
but I was able to pull 7k on patch so you be the judge