Many fine players release their pinky and perhaps ring finger from the stick here. Of interest is the fact that in photos 1 and 2, you can see how my upper arm is near parallel in position to the stick itself. The angle between upper and lower arms, though, has increased.
The sensation is of moving the cue through the stroke from elbow down, however, and quite important, my upper arm is not restricted with rigidity on the backswing, it moves.
Far too many beginners hold their upper arm in check in a vain attempt to create a pure pendulum movement with the lower arm. The pros say "like a pendulum" instead. A true pendulum would make timing the bottom of the pendulum, the hit on the cue ball a difficult challenge. The player who tightens their arm frequently gets unwanted draw or topspin on their stroke.
It bears repeating--stroke the lower arm in a pendulum like motion or throwing motion allowing the upper arm to move on the backswing, in the same way you would toss a ball perfectly straight and exactly to where you intend without conscious effort. Watch your pool skills soar immediately!
The pool myth of pure pendulum has persisted for years, so do not take my word for it--heft a pool or other ball and toss it to a target along your pre-planned arc, but hold the upper arm rigidly with constricted muscles and note your results. Now toss to the same target again with a free moving upper arm. See the difference?
It is on the forward move that the upper arm will return to its starting position and move but a few inches forward, giving the illusion on short shots of a pendulum stroke and an explanation of the pendulum pool false theory.
