No matter how perfectly I do my rotations, help the party with information (when relevant to do so), perfectly dodge every single AoE in the entire dungeon, I still almost never get a commendation as monk. People have a bias towards tanks and healers even if they're just doing "fine" (as opposed to nigh-perfect). Personally, I have a bias to ninjas that use Goad judiciously on me or others if their do need the TP, and bards that use songs properly when relevant, so long as did they okay in other ways. Else, I commendate whoever I believe did best in their role.