The Martial Spirit is a book that I can't see failing to appeal to any thoughtful person who has spent sufficient time in any martial discpline. The author has himself training widely in what on the surface appear to be very disparate arts and has trained for a sufficiently long time to give us a perspect that few are able to offer.
While I don't agree with all of his conclusions I feel strongly that his opinions were not offered hastily or without careful thought as to their effect on a broad readership.Kauz also is also highly literate and is able to write with a command of the language that few in the genre can surpass.
I would recommend this book to virtually anyone who is interested in the martial arts. It is definitely in my top 10 books on the subject.