[Yoda]

...unless someone does something, maybe intentionally or through bad swing mechanics, it's not likely that their arm will move back without rotation; the golf club dosen't want to swing that way. And it isn't too comfortable, either.

Do something for me everybody:

Pretend you are holding a comb or brush. Now begin to style your hair. Assuming you have some, of course; otherwise, pretend you are a stylist working with a customer.

Imagine you are looking into a mirror and comb away: the front, the sides, the back, all 'round. Use the other hand to help the 'smoothing' process. Note...

1. The hand only holds the comb or brush.

2. The forearms rotate naturally, as they should.

3. You don't think a thing about it.

So it should be during the Golf Stroke.

Unfortunately, many people do strange and unnatural things with their arms and hands and bodies during the Stroke. Usually, these contortions are the result of incorrect concepts. Only when the correct concepts have been learned and applied will the corresponding motions be brought to their natural state.

And only then will you begin to play your best golf.