A swinger uses his entire body to create power to transfer to the ball.
A hitter simply positions his body in such a way to provide a stable base to drive the right arm down the plane line.
Grantc,
I'm afraid this is a myth. And one that may be very counter productive for a lot of golfers trying to hit the ball. If this were true you should be able to hit the long ball without even moving the right shoulder. That is never going to happen.
All great hitters also have a good pivot motion. For some it is very different from a good swinger's pivot. For others it is very similar. They pull from the left side as well. Take a look at Yoda hitting and swinging. The part from feet to shoulders is basically inseparable!