Yet, if you watch closely, you will see that his elbow does not drop until after contact with the ball.
I know that different things work well for different people, but for me, their 2 keythings for my stroke. 1st, shoot with a very relaxed grip, second, DO NOT drop my elbow. I lose a lot of accuracy when my elbow drops. When I check to see if I am hitting the cue ball where I am aiming, I can always tell if my elbow is dropping by how accurate I am.
Nobody is disputing that most people elbow drop after contact...We are disputing the commonly held notion that dropping your elbow at all (post contact or otherwise) is inferior to a static elbow.