Through traditional teaching methods people have learnt various myths regarding the positioning of the body in the golf swing. Such myths often result in making the body vulnerable to injury while inhibiting the body to move freely towards the target having a direct impact on ones direction and power within the golf swing.
When observing a simple throwing action, one would start by drawing their arm back whilst at the same time loading their weight onto the right foot. At this point the right elbow should be free, and away from the body. The power of the throw will then come from a reverse direction of the body, driving off the back foot onto the front foot. This will cause one to lead with the right side of the lower body enabling one to have more power when the ball is thrown. It is this rotation of your right side that will clear the way for your arm to pick up speed, releasing the ball with the arm extending towards the target.
Similarly a boxer who throws a punch will generate more power using a full body rotation with his right side than if he just used his arm to throw the punch, without using his body. If we relate this to the golf swing, during the backswing one needs to feel as though ones head is free to move away from the target and towards the back foot, which is your preferred stable base or pivot point. Where golfers tend to go wrong is that they follow the myth of keeping their head down and end up swinging around their head making this the pivot point. The sequence of the downswing starts from your glute muscle which in turn fires the right side, resulting in the drive off from the right foot (lower body) followed by the right knee and in turn, the right hip. If one keeps their head down this will limit their rotation towards the target, as opposed to watching the ball fly in the air enabling more rotation of the right side. It seems obvious that one would use their more dominant side to gain the most power and control when doing anything. Why then, do golfers use their left? The golf swing requires the same principle of benefiting more from using ones dominant side. Similarly the same principle applies to the left-handed golfer, the only difference being that they will use their left side.