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The purpose of the golf swing is to hit the golf ball as far and as straight as possible and there are many theories on how to do this. One aspect of the swing that most theories have in common is that the golf swing should be as wide and as high as possible.

This wide swing arc encourages the golf club to travel further during the swing, therefore as the club approaches the ball, the club head speed will have gradually increased due to the distance travelled rather than a forced power action which can ultimately end in a poor connection on the ball.

A wider back swing can cause issues because the club is travelling further than usual. The speed is increasing as the club gets longer, and therefore consistency will take some work. Once the right drills are completed and the feeling becomes more familiar then the change in the swing will be better.

To perform a wider back swing, the fundamentals must be perfect:

The left arm should be straight at set up with the club as an extension of it
The posture needs to be strong and athletic with a straight back and good hip flexion to allow for a big shoulder turn and enable the flexibility of the body to rotate with the hips
The width of stance needs to be right as too wide a stance will hinder weight transference

With these basic set up fundamentals in place, the golf swing can now perform what is required. To create a wide arc, the left arm should push back away from the ball keeping the club as its extension, so no wrist hinge is necessary at this stage. The left arm should remain straight throughout but relaxed so any tension doesnt hinder the rotation.

As the wrists then hinge naturally, the left arm will lift as the shoulders rotate encouraging a high left arm position almost perpendicular to the ground. This movement is trying to get the club as far away from the ball as possible. Be aware not to laterally move your body and straighten your posture. Now the swing is higher and wider and travelling on its furthest path to the ball helping the gradual increase of club head speed and resulting in more distance.

Before performing this movement, make sure your body has the capabilities to do so. If you feel you cant get as high to the top of the swing, it isnt a problem because a three quarter swing with a wide takeaway will still produce a lot of power.

Swinging the club as wide as possible is great for those looking to generate power but the procedure to do so needs to be perfect. Any lateral movement away from the ball may actually help your width and height of swing but it will hinder your timing and ball striking.

Creating width on the back swing is ideally what all golfers want to do but make sure that you are not stretching both arms away from the ball because this will limit your wrist hinge. Also, the length of swing will be much shorter as the right arm needs to bend with just the left arm staying straight.

Extending the length of your driver could possibly help the clubs swing arc increase, however, the best and most consistent way would be to adjust the mechanics of your swing so you can reap the rewards with every club in the bag.