wtf? so your saying that for the 3minutes after Minato sealed the Kyuubi's chakra, between then and his death... he mastered it? lol I guess you don't even know that at that time the kyuubi's yin was attached to minato's almost extracted soul...and he himself was still alive in the Unpure world.
@ the bold: lol you people are still using dumb logic, in that case, Minato Never had KCM while he was alive.
What you didn't know Itachi had kotoamatsukami and Izanami?
Bro, no matter what feats blondie pulls in the next few chapters...as long as he has no counter for Koto and izanami....Itachi > Minato.