If parsing is needed to clear challenging content then why is it not in the game?

[Underdog2204]

I mean, you can see if you have enough DPS, the boss dies. If he doesn't, and you fail to kill adds/it in time and it enrages, then clearly your dps isnt high enough.

Mine or someone elses? Or multiple peoples?

You can't answer any of these questions, which is kinda silly since there are 4 dps in the group and none of them can see how they are performing on an individual level. You can only improve yourself individually and you cannot do that if you don't know there is something wrong.