Knowing nothing about Samurai's history and/or tradition, I can only take the "philosphy" from this book.
Death is considered the only very important thought, around which everything else must dance in one's life. Death is our ultimate destination, and everything must be done in view of that unavoidable event. I can agree, but I cannot wholly share the attitude of a Samurai about it, since I believe I can leave more seeds and fruits through my life than through my death. I can teach a lot with the way I approach death, of course, but I don't believe everything about me is decided in that one moment.
A Samurai celebrates death through his whole life; I'd rather celebrate life through my own death, but it might be just points of view and in the end we might as well mean exactly the same thing.
What I disagree on without the shadow of a doubt, is the view about women: weak and unable to raise children; creatures to be ashamed of, to hide, to get rid of as soon as possible... Mr Yamamoto should know some of the men and the women I got to know. Then he might change his mind - or commit seppuku :)