I have a small pile of martial arts instruction books in my library.
[Even if someone says "you cannot teach swimming by books", I disagree. At least, you can teach what to expect, what to do, and what not to do, to a never-swimmer. These basic instructions (verbalized, or written in a "book" form) can save his life.]
Some of the instruction books are about Brazilian jiu-jitsu (BJJ) . The art (BJJ) revolutionized MMA in early 90's. Contestants trained with BJJ dominated the MMA contests for some early years, proving efficiency of the art in the MMA ring/octagon.
In response to the success, demands for learning the art also increased. And the demands resulted in several decent books for teaching BJJ.
"Mastering jujitsu" (Renzo Gracie) has a decent BJJ history section and clear theory sections. The book was very helpful to understand the thinking (theory) behind the act. You'd be astounded by the smartness of the thinking. The calculating art of BJJ is a world apart from Adrenalin-fueled hay-maker fight.
"BJJ self defense techniques"(Royce and Charles Gracie) is more practical book for a beginning practitioners with pictures on techniques.
"BJJ theory and technique"(Renzo and Royler Gracie) has a well-written and concise history and theory section, and photos for techniques based on practitioners' levels. In this book, the "key positional strategy" is clearly and concisely stated, and it helped me to understand and appreciate the game of BJJ greatly.
Here I am adding another decent BJJ book, "Mastering the 21 immutable principles of Brazilian Jiu-jitsu" (Paulo Guillobel), published in 2015, to the pile in my library.
This book may not be a book for a beginner of BJJ. But it is a kind of book that would benefit readers with a certain idea about BJJ, and active practitioners who know what they are talking about, greatly. I recommend this book for these people.
[How-to books are written with target readers in mind. If you are among the target readers or not should be clear in the beginning. I don't think it is fair to the book when a "wrong" reader complains about a "wrong" book for him.]
[The book cover]
I like how-to books that are actually useful and helpful to appreciate the art more. I am collecting good ideas to convey core notions and practices of a physical art.
Good BJJ teaching/writing should be translated to good teaching/writing for tango, for example. When I write a book, I want it to be a good/useful book for the intended target readers. Anyone can write an essay, but communicating the art with words in order to be reproduced requires more.
In terms of verbalizing the core notion and teaching the techniques in the book form, BJJ is ahead of Tango in my judgement (at least in the forms of books easily available in English. I cannot say about Spanish/Argentine books).
I don't have to reinvent wheels. If there are good ideas in BJJ or other sport/art teaching books, I'd borrow them, for the sake of propagating the art of my interest.