Niwashi, you keep bringing up these hypothetical situations, I AM a BRD, who has done all the content in the game repeatedly, I apply Ballad and Foe's when and where it is needed, and am still almost always at the top of DPS, running a meter in no way impairs my ability to use skills when they need to be used...

Anyone who would be distracted so much by a parser that it would negatively affect their performance, are the same people parsers are needed to identify, those incompetent at playing their jobs.

In many instances where some DPS check isn't met and the party wipes, someone(s) always says "Why is Damage so low, anyone running parse", no one knows who to point the finger at, until someone says yep

"BRD xxx, MNK xxx, DRG xxx, BLM xxx"

"oh hey (Job) you are pretty low on DPS"

"oh crap, really, I'll do better this time"

his DPS improves and win fight.

This happens all the time, some people need a kick in the butt, they get distracted or mess up their rotations and don't even know how bad they are doing until someone tells them, then they get in gear and perform better.