This is a shoulder scan that clearly show the space that is stretched when the arm is raised.
This shoulder image clearly shows the space that is stretched when hanging.
JRE #1062 - Joe Rogan and Dan Harris talk about shoulder impingement and stretching
The techniques outlined in the book have been featured on the JRE podcast.
Famous Physical Therapists Bob Schrupp and Brad Heineck describe a new and simple technique for treating shoulder pain. Recommended for shoulder impingement, rotator cuff tear, and frozen shoulder. Hanging from a bar! Developed by an orthopedic surgeon, John M. Kirsch.
These guys are pretty funny and have a lot of great videos to help numerous issues. They reference the book here as well.