Feel the top of backswing with a heavy object
To feel the top of the backswing, the speaker uses a heavy object such as a medicine ball instead of a club. The motion mimics dumping a water bucket or throwing a bag of sand over your shoulder, and the weight naturally causes the hands and trail arm to fold and roll over. He points out the lead arm ending on the shoulder line and the club sitting on plane.
Channel: SagutoGolf
Watch official source at 2:09Why this context matters
Demonstrated at home using a heavy object (a person, 'Roger', stands in for a medicine ball).