So many of you have probably seen the exploit about killing members of your own faction, in this thread: http://www.mmowned.com/forums/world-...r-faction.html
While it's fun to do this, it actually does have a more practical value--it remains during arena. The damage from the disease removes polymorphs, blind, sap, hunter freezing traps, as well as other various break-on-damage cc's. While the disease only lasts 30 seconds, death knights can summon their ghoul during partner cc, and have it leap to their cc'd partner, breaking the cc. This is especially helpful in 3v3 and 5v5, where games last less than 2 minutes. I tried it out with my 3s team last night, and it was absolutely game breaking. The only downside is not being able to have a ghoul until your partner gets cc'd, but as I mentioned, this isn't that much of a biggie in 3v3 and 5v5 where the games are so short that most teams blow their cc's right at the start.
Good luck and have fun.