Sergio,
I'll take a stab. But someone else may give you a much better answer than I ever could, because I don't actually know. I only have theories.
What I do know is that Natural Turns were the norm back in the 1700's when Ballroom Dancing first started appearing, mostly in the form of fast waltzes and polka-type dances. Natural turns are easier to move around a CCW floor, because you can under-rotate it. If the floor was to move in a CW direction, you'd need to over-rotate your Natural Turns.
So the CCW direction of the flow of traffic seems the natural result of the right-turning basics. And turning the basic to the right is easier when the lady is offset to the man's right. I suppose, then, the real question would be: How did the convention of having the lady offset to the right and turning the basic to the right ever begin? Couldn't it have just as easily been the other way around?
I've heard very curious theories, such as the man wearing his sword holster on his left side, but they seem pretty far-fetched to me. I'm more inclined to think that it's just the way it happened. After all, it had to be one way or the other. It's probably just arbitrary. This may not be as romantic as the sword idea, but it's something I for one can swallow.
I hope this helps.
Sincerely,
Jonathan
[This message has been edited by Waltz123 (edited 07-26-2000).]