Having partied with a 600+ DPS MNK quite a bit recently (650 when we're all being tryhards), it wasn't so much parroting as just waiting for something substantial. It's not a number I see people hit much outside dummies.
"Substantial", however, came since my posts from the very same MNK mentioning he's most likely keeping his lead in his coil group explicitly because the resident NIN doesn't weave potions into his fights. Hasn't been tested, but if he's willing to say it about his own DPS being passable, I'll believe it.