Board Thread:Theories and Speculation/@comment-33286580-20180609133213/@comment-33286580-20180609185858

@Killman

Sasuke used it once with Lee, but only because he was in a pinch. i have no idea Madara ever copied anything.

and Six Paths knowledge was certainly passed down by Madara to Obito. at that time Madara didnt have Rinnegan so he couldnt demonstrate him and it is more or less implied that Obito told Nagato about the Rinnegan abilities.

@Legion

Mifune was never placed in Koto. he was placed in Genjutsu by Sharingan, and Uchiha Shisui's Sharingan Genjutsu was said to manipulate people without them knowing of it. it is what Mifune broke of.

Koto is MS jutsu. MS as said is awakened by very few and even then only Shisui had Koto.

I never said they can't copy, but the copy mechanism is more or less unused.