It just seems a great deal of engineering to go to and to be counter-intuitive. It also didn't seem particularly likely to be an historical solution.
Portraits don't show much, however, and the extant Italian gowns are not of this style. And then I found this gorgeous close-up picture of the lacing on Fede Galizia's Judith. It was taken at the Ringling Museum in Sarasota Florida by Cindy Lyon (sea95lion)/ Signora Ciana Leonardi di Firenze. You can find it and several other amazing detail shots of this painting in her Flikr stream . She was gracious enough to let me link to it (see the caption of the picture for the link.) Take a look at that, huh? Eyelets sitting behind heavy embroidery. Distortion on the edge as they pull, and a slight intertwining of that looks to be a doubled lace. How COOL is that?
Ian's shoelace site has a diagram of ladder lacing for shoelaces that creates crossed/intertwined center cords very like what I think I'm seeing here. It puts the thick ridge on the outside, but it can be reversed and put on the inside. There's also a simple bar lacing that gives the same look without the interlace. I figured I'd put eyelets in my new brown dress and try both. What I'm hoping will happen is the extra side ridges for the ladder lace will create a more stable and secure lacing with less pulling, but I'll have to experiment to see.