Hands Down *
is about r-e-a-c-h-i-n-g the hand d-o-w-n before spiraling the shoulder muscles that assist in spiraling the arm.
Keep in mind that in this exercise the spiraling of the arm is initiated by the muscles of the shoulder and back.
Reaching your hand down before beginning, initiates a nice stretch of the arm muscles.
Tip
Make sure your shoulders are relaxed and down. Do not push them down, just let them gently fall.
You can test this out by resting your hand on the opposite shoulder, to find and release any tension in that shoulder.
Also, look carefully at the video to see that the hand is the last thing to turn.
Caution
Be careful with your arm . . . do not over-extend the elbow. There should always be a very tiny bend at the elbow.
I recommend that you study this in the mirror, and practice doing it with your eyes first open, and then closed, until you feel the ease in your elbow without having to look at it.
At first when we practice certain movements, we have to apply extreme deliberation to the process.
But after a while, muscle memory kicks in, and you will be able to do this without overly thinking about it.