The elbows in the golf swing are critical. You must keep them working towards each other during the entire swing. If you allow the elbows to come apart, many different problems can arise.
One common problem when the elbows separate on the backswing, is having your back elbow trapped behind your hip rotation on the downswing. This is a big loss of power and will force the club to flip into the ball.
Another common problem, is the elbows separating through impact*. This happens when your hands and arms took over, and are trying to pull the club through impact, vs. allowing your body rotation to bring your arms/club (with the elbows close together) through impact.
One final problem, is the elbows separate through impact and the front elbow bends out** and “Chicken Wings” as you rotate through. This opens the club face and can cause you to block your shots or may cause you to flip to save the shot.
Well, the answer to all these problems, is to set up with the elbows towards each other to begin with, and keep them working towards each other during the entire swing. This will also force you to use your Large Muscles (the shoulders in the body rotation) to control the arms and club.
In Ben Hogan’s book, he has an illustration showing the arms close together, with string wrapped around them as tight as possible. This shows how important it is for the arms to continually work towards each other during the swing.
One last note, Tim Clark is one of the best examples of a golfer that uses his arms correctly and is part of the reason he’s so consistent with the game.
(Hint): Pinching your elbows towards each other during the swing wakes up the Large Muscles to do their job. We want the shoulders to control the backswing and the entire body to pull those “pinched elbows” back down in front of our body as we turn through! This pinching helps defeat the hands and arms from taking over and connects the arms/club with the shoulders.
* The Elbows should be close together and point back at your hips through impact (hips will be slightly turned rotating).
** The front elbow should point back at your front hip through impact (front hip will be slightly turned rotating).