I used the rear elbow as a point of reference because I think there are two ways of making the adjustment based on what type of swing he has.
Some guys start with the barrel out of plane, and move into plane as the hips are opening (and creating separation) before hands/arms bring barrel to the ball.
Some guys start with barrel already in plane and use a different timing mechanism to delay upper body/barrel.
I think he falls in the latter catagory. I think if he elevated the rear elbow a little more (or delayed it's descent), it would create his timing mechanism.