Quote Originally Posted by Abdula
I think perhaps you have it the other way around and he began utilizing others people's bodies because his own was so frail and weak, because regardless of whether he can use other bodies or not no one would render themself completely helpless. And as Jiraiya implied, of the three, Konan, Yahiko and Nagato, Nagato was by far the strongest so something must have happened to make his body the way it is.
Are you saying that Nagato is the ultimate nin and genjutsu master because he's so weak and frail? I guess that could make sense.