No question as far as my thinking is concerned, it was Chapter 4. Questions were answered in Chapter 4 that I have had as long as I can remember. I especially think that pressure in the arm pits will contribute greatly to the amount of pressure needed in the arms. Also,and very important, the thought that I do not have to concern myself with lag and trying to, GET THIS, KEEP PRESSURE OUT OF MY ARMS has been eye opening. A person can play golf a lot of ways, but unless they can produce it with consistency, it is not of much use. I have shot under par trying to swing with practically not pressure in the arms, but trying to produce power that way is limiting to say the least. I am sold on the whole program here. I just wish it had come along when I was younger.