User blog comment:IamJakuhoRaikoben/Chapter 323: The Shadow That Comes And Goes, Review./@comment-5668006-20130316051818/@comment-36.68.249.25-20130316074726

eddiej, as you asked, "why wouldn't he remember his own strength from 7 years ago?"

my theory is that F rogue didn't expect for gajeel absorbing his shadow magic (which means, before this gajeel would never absorbed his magic)  that's why at the end of their battle, the shadow (who controlled rogue) said "this is not gajeel i know"