http://www.golfdigest.com/magazine/2...famous-golfers

http://media.worldgolf.com/wg_blog_m...10-08-06-1.mp3

Drew,
What is the left shoulder hinge pin?

If that includes the scapula, ribs and humerus joint as one hinge I would agree.
You mention the primary assembly unit working at one RPM.But it has to match with the PIVOT RPM. There is no use swinging the arms if it's not in synch with the body.
The "connection" in a physical sense to the PIVOT is through the left scapula and ribcage.


Bernt,
Agree that clubhead is moving at a different rate than than shoulder, different from the wrist and different from the pivot.
RPM is speed and a measurement of tempo not rhythm. Rhythm as you correctly describe is the pattern each part of the machine's rpm's blending together.

dlam,

it's how the rpm's of each part of the machine work together

I thought that was very well said.

dlam,

I thought said it very well here:

it's how the rpm's of each part of the machine work together

Here's the abridged version of the MacDonald drill type action.

http://www.youtube.com/watch?v=YLD70YrjZD4

This would make a nice clip to show during a presentation of some sort or other. Motion maybe.

Drew do you know the origins of this drill? Vardon , Mehlhorn, MacDonald ......it sure works who ever it was.

I wonder if Fred would have been forced to do his tap dancing with soft spikes today :eh:

We Got Rhythm
 

http://www.youtube.com/watch?v=gjmpo...ayer_embedded#!

Drilling for old
 

Ginger Rogers?

Although Vardon came before Mehlhorn (who I got to work with briefly) and Macdonald, both Mehlhorn and Macdonald incorporated them effectively into their teching. the origin is lost in the mist of time.

Lets Go Around This Together
 

Not each part, but specifically the Lever Assemblies (Left Arm and clubshaft) regardless of Clubhead Extension Velocity (uncocking of the left Wrist).

Lynn's video is very good at describing the rhythm and the hinge action in chipping. I like the analogy of the merry-go-round. In the chipping the slowest RPM would be the left shoulder and fast RPM would be the clubhead.
I believe the full swing is a different animal.
The full swing requires a good pivot, the torso has the slowest RPM, slower than the left shoulder, and thus should be the regulator of the total speed(tempo) of the swing. Just like the drummer of a band dictates the speed of play the other band members.
I believe the initiation of the swing, would be better of at the core perhaps the pelvis turn, maybe the shoulder blades and rotation of shoulders , or the head turn. This would keep the swing motion in rhythm.