During the practice of 'ran o toru', a free style method of practice used in the Kito Ryu Jujutsu system, Iikubo would repeatedly throw Kano, even though he was thirty years older than the young man. Kano began to analyze the process of throwing, to see what makes it effective. During this analyzation, Kano came upon three discoveries. Once he implemented them, he was capable of defeating nearly anyone. Upon relating these concepts to master Tsunetoshi Iikubo, he was admitted into the Okuden, inner traditions, of the Kito Ryu, and allowed to view the scrolls and books of the system.
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