User blog comment:IamJakuhoRaikoben/Chapter 388: Erza vs. Minerva, Review./@comment-133.101.167.124-20140616080800/@comment-24800928-20140617002913

well the armor didnt giver her physical strength like a power boost or something pertaining to magic, but it was kind of a physical strength born from or akin to emotional strength and confidence. The armor made her feel like she didnt need armor at all, since it isnt actually armor, and it gave her the power and confidence to fight. Of coarse it became B.S after a while.