[gmbtempe]

As I understand it:
that clip may contain "endless belt" but it can not be seen in the clip.
I think a clip from behind the golfer so that U can see the plane and the left arm pointing below plane is a view of endless belt.
As I understand, the "belt" is the club moving AROUND the left arm and only exists , to the amount, that the left wrist is cocked.
Hold the club in a normal left grip, wuth a LEVEL wrist. Swing one armed back and forth and see the club FLAIL outside the left arm.
Since the flail is dependent some cocking remaining in the left wrist I see how the coordination between #2 an#3 is critical. That may be taking it to far for this question. LOOK at a behind, plane angle swing and you will see the answer.

I am very much a novice in this stuff and I am sure you are right....I just like how it looks like his hands are running at a constant speed in a straight line yet when they clubhead turns that wheel it looks like it accelerates. I bet this guy hits it a ton yet it looks like he is not forcing anything.