Bards give +mit on their defensive buff if AA spec'd for it(Shadows, second line), some priests have +mit attached to a ST buff that usually goes onto the tank(i.e. warden with character trait), some classes have +mit buffs that hits the entire group(Conjurers, Geotic Rune) and there is a purple war rune usable by priests(Foundations of Adamant) that gives a permanent +mit buff to the group and stacks. There's more, but the point is: there's lots of other sources of +mit and it's really not that difficult to raise.