Although there are things to learn in here (considering it's a book from the current doshu so it carries quite the authority), the explanations can get very repetitive, and lack a lot of important details when showing several techniques. I know there is nothing like a good sensei and some practice to learn martial arts, but that's all the more reason to be thorough when writing a book with techniques.
All in all it's a nice book, but others seem more relevant to me.