Would a VR-type practice dungeon be a reasonable compromise?
I believe there are honest players out here who feel the need for parsers to gauge their performance. Let there be no doubt about that. What's being planned for 3.2 sounds like a step in the right direction, but only a step.
I believe there may be a middle ground that will satisfy those who want to experiment and test their performance as well as disabuse those of us who are averse to the potential drama a parser in dungeons/raids can harbor.
A VR dungeon, I believe, seems like something that would more readily replicate actual dungeon/raid mechanics without the pressure of wiping. A Light/Full Party can set the difficulty levels, go in to practice whatever they feel the need to work on, and receive an analysis on their performances afterwards.
I do believe something like this would assist in people who genuinely want to improve their job performance (Key word: want).