TIL that expecting lvl 60 players to do higher DPS than lvl 50 ones is elitist.

Enmity meter
Problem with that is it's all relative to the highest hate. Ignoring everything that affects it, then yes, you might get a general idea about the players against a single mob, if the gaps are big enough. But what if the bars are relatively even and you still hit enrage? Clearly it's the healers or tanks not doing enough DPS, never mind the fact that every DPS was performing under par. Even the guy whose bar is three times longer than the shortest one might just barely be above what's expected.