Saltire kilt's tartan??

[M. A. C. Newsome]

I wonder if there's something simpler at work here. Imagine the fabric already pleated, and then overlayed with a stencil, through which a dye, ink, or "fading agent" of some kind is applied. Is there any difference in the texture of the fabric where the elements of the pattern appear?

Yes, a kilt like this could be made in this way, but that's not how it's done here. The House of Edgar weaves the pattern into the cloth itself. I've seen the looms.

This is also what Steve, I, Paul and others have already said. Trust us. ;-)