Our old friend Pete is still grinding away, and while his swing has greatly improved he is still fighting tendencies that have been present for a long while as he contends with back issues. The main thing that a stiff, sore, painful back have on the swing is to restrict the separation of the upper and lower trunk movements during the full swing. The brain is wired to avoid pain, and even when the back is feeling OK it is difficult to move the body at full speed into places that previously have caused problems. I know this for a fact because I wrestle with it myself every day, and I can see in Pete’s swing that the things we want to see are difficult to achieve because the body simply avoids the positions, and it takes a huge amount of focus and physical effort to force what you would hope would be more natural.