While Matt pinpoints his biggest problem as his release, I see some things that make releasing the club properly problematical, especially the instability of the lower body in the backswing. Matt has a large amount of hip slide to the right from P2 to P4, enough so that his pelvis is not in position to initiate the forward swing properly with the rotation of the right -side hip rotator muscles. Because his pelvis has so far to go just to get back where they started it is no surprise that his upper body leans to the left to begin transferring pressure from right to left. In addition, from an on -plane position at P3 Matt stops rotation his forearms and pulls his right upper arm and shoulder back behind him, causing the shaft to cross the line and pushing the upper body to the left before the hips have a chance to lead the movement. I suggest to Matt that he work hard on keeping his hips in the face-on box in the backswing by first concentrating on keeping pressure on the inside of the right foot by pronating the arch of the foot against the ground, and then by placing something heavy like a bag stand or a chair on either his left hip or his right hip to try to feel what it is like to not slide the hips. If the hips stay more in the box Matt can improve his backswing plane and not cross the line by supinating his right forearm (rotating it clockwise) continuously from P3 to P4, which will cause the right shoulder to begin external rotation and the upper arm to stay more in front of the chest. Another benefit of stabilizing the hips is that it would make keeping them deeper in the forward swing much easier to work on since they wouldn’t be so busy trying to slide back to the left after losing so much ground with the slide.