FM, I not sure I'm exactly following you here, you seem to be suggesting that it would be possible to make a saltire design on the pleated portion of the kilt by careful pleating using the Saltire Tartan (6152)
the "Saltire" sett tartan which was specifically designed to be able to accomplish something similar when the kilt is pleated "just so", which I believe it could accomplish.
This would not be possible as you cannot change to horizontal positioning of the tartan stripes in order to make the large diagonal cross, and I don't believe that the tartan as registered was ever designed to accomplish the cross as you suggest but more likely as the background to the rather more clever weaving.
As Matt has said the fabric is specially woven with small section of white bands in strategic places to enable to pleats to be done in a "Saltire" shape. when I visited Hamish last year I did indeed have a look at his saltire kilt as I was fascinated by it as well.
Perhaps I've misinterpeted your meaning,but I can't see what you are getting at if you're not content with Matt's answer, and as an aside would it be possible for you to resize the image as it's throwing the page size and making reading the posting difficult without scrolling sideways....