If the DK has a str trinket popped (the pvp one for example) he can still crit 25k or more... I get 20k+ crits from dks all the time without them having vengeance, or a trinket . Thats still alot for a class with that amount of survival imo. Vengeance not proccing is just a fix for helping people in bgs who don't have anyone in their team who dispells vengeance, other then that DK stays very strong and hard to kill...