My favorite observation while checking out the book so far is the illustration that Kelly uses when describing the hip joint. He uses an African Shillelagh (club) to portray the femur and then uses some cloth to demonstrate the hip joint capsule and the effects of a slack capsule joint compared to a tight capsule joint (pages 50-51). This has helped me understand some of the things that can go wrong in the hip joint. Strangely enough just weeks before my arthroscopic hip surgery to fix a labral tear in my own hip joint, I traveled to Kenya and met with some Masai people on the Masa Mara. I did some Masai jumping and bought one of those clubs from them. Despite all my focus on my hip at the time, it never registered to my mind that the club I bought looked just like the head of my femur.
And now that I am fully off topic...here is a video I made of the Masai, just because that was a really cool experience.