I don't know that I ever finished it. I was doing it for the Guthrie Scottish Rite College of the Consistory correspondence course, but petered out pretty quickly as life took over. :)
The book, however, was Secrecy in Japanese Arts: “Secret Transmission” as a Mode of Knowledge https://www.amazon.com/gp/product/1403965501/ (Price has gone up in the 10 years since I bought my copy…)