It makes sense to me. The Thudbuster is the only change to my bike. And think about the action of the seat in regards to the rest of your body. As the seat goes back, your body is being pulled slightly back from the handlebars. It's slight, but the constant movement is enough to change the position of the arms and shoulders. You are basically tugging from your torso through your arms to your shoulders.

Mlau, where's your thread?