Casso, option A for sure. I believe they are designed so that you can push on the handle with the palm of your hand, without always having to grip it tightly. It justs feels more natural.

I actually use Option B - what a weirdo, hey?

I find that the ball on my palm (the base of my thumb) sits nicely in the concave bit of the handle and my fingers wrap snugly around the bulge of the handle. Seems to fit perfectly in my hand that way, and your right DJ ... I seem to have more control over twisting of the blade.

I thought I used it the natural way until I used the paddles of two separate friends (who both used it opposite to me) and then I thought - oh oh, maybe I'm the odd one out. Never mind, it's comfortable to me using it "in reverse".