User blog comment:ShonenChicoBoy/Shonen's Regimen and Tonic: April 2015/@comment-136273-20150417110210/@comment-136273-20150417145657

Yup, I was speaking specifically about the "overpowered" part, not Mary Sues as a whole.

Mary Sue(ish) characters are bad, full stop. It's just that I can completely ignore a fanfiction when they run rampant, but in an RP it quickly becomes an issue.