This is all very interesting for practitioners, depending on their level of knowledge of the historical or curative sides of the art, but almost none of the information in the book is, in my humble opinion, practically applicable for such a reader. The herbal cures would be potentially deadly without expertise, the healing extracts are too fragmentary to be of any coherent use to any non-expert, such as myself, and the moves shown are only shown as individual ones - although the bunkai may enlighten, they are not ones that will instantly enhance your fighting prowess by being woven into others.
Overall, it is a very interesting book in terms of the insight provided into the internal world of gong fu, but can only really disappoint if you are looking for the 'secret master texts' of the ancients or any knowledge of vital point strikes or healing, and leave you regretting you didn't get some other book dedicated to it.
So, before getting this, consider what you want from it. As an introduction for the dojo-reared karateka, it is excellent, but as a key to perfection in karate, you may be disappointed. I would imagine this was kept by Masters not to illuminate secrets, but to encapsulate their knowledge.