I don't see so much difference.
Brian Elliot says "In strokes where power is required (such as the service and groundstrokes), a number of body segments must be coordinated in such a way that a high racquet speed is generated at impact."
Agree .. and It's exactly what i would say here:
"The kinetic chain energy as a sequential sum of its segments energy, it's a myth. Each segment affect the operation of the other, don't add"
You have right, i forgotten all muscles involved around the shoulder joint.
If the technique is correct, the swing itself is a constant practice for arm muscles. Surely we would develop the speed of the arm, and not strength.
Thank you Sys
Wilson BLX six-one TEAM + 8gr lead - Gosen Eggpower 23/22 Kg