Hi Tony,
I haven't read Manuel De La Torre book Understanding the Golf swing, but maybe I'll try to find a copy. I know his work is widely appreciated by other golf instructors.
I like the idea of keeping it simple, I think the goal for each golfer is to get to a place where they have a few simple keys that make their swing work. The problems arise when your swing is not where you want it to be and you want to fix a part of the swing that challenges you.
When it comes to the hand vs body discussion, I think it's hard to make a firm rule that something always drives. Developmentally, we often move our bodies to help us look and reach for things. So there is some merit to the idea that the body will follow what the hands want to do. But Neurologically, if your body is functioning correctly, the body will activate from the core outward. Many people feel this and interpret this as a feeling of the body leading. They both happen and are both accurate descriptions. That's why I like to teach a few things. What do the arms do, what does the body do, how do they relate to each other. I find that understanding each side of the movement can increase your odds of making a breakthrough and finding one of the simple keys for your swing.
With the backswing, a struggle is often a sign of a power source issue in transition. Often from loading the arms instead of loading the body. If you want more direct advice, feel free to post a video of your swing and we can investigate what might help you.
Happy Golfing,
Tyler
