User blog comment:FairyRaven/Fairy Tail Chapter 401: Igneel vs. Acnologia, Review and Commentary/@comment-24467372-20140922162609/@comment-24546844-20140922170110

I too think the one-hand thing is a bit of exageration on the part of the fans. It's obvious that he only uses one hand because he likes to hug the book with the other. But I'm sure he'd fight more serious with both hands exactly because he doesn't have the book. Maybe his other hand can use another type of magic, a more destructive one.