User blog comment:IamJakuhoRaikoben/Chapter 270: In a Night of Falling Stars, Review./@comment-4223231-20120211023847/@comment-4792864-20120211024145

Gray's promise doesn't really mean anything. Cana promised that she would defeat Bluenote during the Tenrou Island arc but she was ultimately defeated (rather shamelessly, if I may say so myself)