As for legitimate creepers, it would be nice if they too could reform and stop posing a danger to others; unfortunately, most of them seem to be actively hostile towards other people and lacking in empathy, so this is not a likely prospect.

I think your confusing what John meant. Learning PUA/Carnegie doesn't change someone's goals only the means. A legitimate creep who acquires better social skills, doesn't become a normal non-creep, he becomes a charming sociopath.