Board Thread:Rebirth: Applications/@comment-1875854-20141001230515/@comment-1875854-20141014020139

Where did Madara hear of it from? And, it does. The ability to force his brain to open gates helps with opening them faster. He still had to master them. Gekijou has devoted his whole life to it. That's literally why he was born. To learn taijutsu.

Iwa didn't "learn" it from anyone. They know the basic concept, they have heard about it (in this app). So they allowed someone who they were training to be a taijutsu-specialist and jin try learning Eight Gates. He's spent over 20 years on this.