Board Thread:Versus Debates/@comment-27418151-20160108230836/@comment-25122992-20160111141827

Firstly, Fire Seal Jiraya used is impractical during the actual fight. If Jiraya gets caught by Amaterasu and tries to seal it, his arm/leg/whatever was hit would already burn out before he finishes, so a severe injury as a result, which already gives his opponent a significant advantage, and if he doesn't get caught, he just wouldn't use it. Secondly, Amaterasu and Fireball Jutsu didn't cancel each other out, the former absorbed (or actually burned) the latter, and Sasuke would've find himself in the middle of raging flames if Itachi hadn't put them off when he closed his right eye.