Here is a snippet of a video of Gary Edwin demonstrating how he shifts his weight.
For a man of 60+ years of age this swing is impressive.
So little effort and tremendous amount of arm and shaft speed.
Welcome any questions or discussion on weight shift here on this thread
This is one of several hundred videos they have on their live website. To see more you can subscribe at http://www.garyedwin.com/
If you want to learn to swing like this you can contact me for further details