Camilo Villegas was a young superstar in the making. He has recently lost his way. Mainly because his swing is very athletic, needs a lot of strength but is in not fundamentally sound.
I believe in reducing unnecessary motion and building a simple repeatable motion. He has way too much extra movement. If his timing is right he can shoot low numbers, but unfortunately he can also shoot himself off the main tour.
He is using a great drill in the video above. If you find your ball starts is curving too much to the left or right of your target then try this drill. It helps you develop a straighter path through the ball.
The ball flight laws tell us that the primary influence on a golf shots initial direction is the club face. The curve of the shot generally comes from the club path in relation to the club face. Therefore if a player has a swing path that cuts too much across the target line then they will likely over curve the golf ball, making it harder to control.
Camilo Villegas is practising his swing path so that he will ahve better control over his ball flight.
He is using alignment rods to set up a track. You can do the same drill by placing tees in the grounds. The objective is to hit solid shots without touching the alignment rods or tees. If you can do this with a square/straight club face at impact then your ball will fly straight.
If you hit the track then you have a swing that is cutting across the ball too much and creating too much spin while also losing power.Hit the inside track before the ball and you are swinging too much from the inside. Hit the outside track and your swing is too much outside-in.
One thing I do like about the golf swing of Camilo Villegas is the length of his backswing. You may be surprised by how short it is. A long swing does not mean more power if it is not done properly. He averages almost 300 yards off the tee. That is plenty long enough! Using a proper shoulder turn, only turn as far as your flexibility will allow you. If you let your arms go farther than you turn you will lose both power and accuracy.
When you practice think of stopping your hands at shoulder height. You will be surprised at the amount of power you will create.