IMHO, I think the working mechanism behind this "trick" is obvious.

Weight movement induces always a(small)steering effect because of the shifting of the lateral surface.
Moving backward with your body means that you are bearing away (a little).

So what you describe is the common zig-zag course passing through waves as the most efficient way.
In big waves that is a must and you use the tiller for that purpose.

Using your weight in small waves in order to have just that instantaneous tiny effect on the very precise equilibrum of all the concerning forces, is a clever idea.

It therefor has nothing to do with rules.