So it took Orochimaru like 10 episodes to do his thing with the 4th, but it only took one move - sexy no jutsu - for Naruto to "defeat" the 4th. Sure it caught the 4th off guard, but it would catch anyone who hasn't seen it off guard.

I say Naruto should have used it against Uchiha Itachi and then 1000 years of pained him a bunch of times when he was on the ground =) I figure after about ten 1000 years of pain one would be too humiliated to live.