My dad spent 3 months in Japan in 1964 and got his judo black belt from the Kodokan – the mother ship of Judo schoools – going from white to black belt in 3 months. I’m not sure if this is the fastest anyone has ever done this, but I figure it makes a nice story that folks might be interested in, and it dawned on me that time is running out to see if there is anyone still alive who might have personal knowledge to fill in the gaps that I don’t know.