TrueJim
Master Black Belt
Actually, that is pretty much what Kano did. He decided Judo needed some rankings, so he swiped the system used by GO players.
Agreed. The thing to remember about Kanō is that he wasn't just a martial artist...he was also a professor of economics, then later an academic dean. Given his day-job as an educator, it's not surprising that he might say, "You know...some of the things we do in the classroom during the day when we teach economics or history or whatever...maybe some of those thing would be useful for teaching judo too?" So the idea of having ranks, giving tests to students to promote them to new ranks, giving students some indicator of their new rank...as an educator, all of those ideas probably would have come to Kanō very naturally. Whereas a martial artist who was more old-school might never have had the idea occur to him: "Gee, I wonder if my instruction would be improved by giving my students ranks?" Now even the local Kung Fu schools in my neighborhood give the kids colored "sashes" to denote their rank.