[dlam]

Don't confuse RPM with MPH. RPM (Revolutions per Minute) deals with the act of revolving (orbit) and the time it takes to complete this action. MPH (miles per hour) is pace. The Clubhead and Left Shoulder can move at the same RPM's, but the Clubhead has more MPH's. The Hips move through Impact at approximately two MPH, the Shoulders five MPH, the Hands 15 MPH and the Clubhead 100 MPH, but all can move at the same RPM's.

Thanks Drew,
Good clarification.

I also wondered what people mean when describing rhythm.
Watching a player like E. Els, everyone agrees has good rhythm, but hard to describe what that is.

Compare to player like K. Perry. Does he have good rhythm? He can play. He appears to take the club back with his hands and arms only then pauses at the top then looks like any other player in RPM in the forward swing.

While E.Els, has a smooth backswing to forward swing, his RPM appears constant throughout like a merry-go-round.
So maybe that's why is so elusive to describe "good" rhythm
There is so many ways to perform startup/takeaway
The "rhythm" of the golf swing doesn't always have to the start at address.