Board Thread:Naruto Discussions/@comment-1512913-20170417105433/@comment-734582-20170420080116

Ravenlot 27 wrote: As I already said, he hasn't necessary had to know about the techs beforehand to use them by himself, it's rather a plot reason. It took Kakashi years if not decades to figure out the Mangekyou part of his Sharingan, and even more years to even use it properly. Even then he must've found it out in order to reduce the cost of using it.

If Nagato had no reason to believe Limbo existed, and had no reason to seek out greater powers, what are the chances that he accidentally finds out about such a powerful technique?