no offense, but his hand is operating that release by squeezing. his neck is crooked, and it is physically impossible for your scapula to engage your rhomboid in that position. his elbow moves vertically, not horizontally, which is the direction the rhomboid would pull it. its easy to see his hand begin the process, and end it. with back tension there is no explosion, and no follow thru.its a very slight movement, and whatever happens after it just happens.