First I have heard that the wires vary (production can vary slightly)... would have to be referencing similar model and year of production of course. SE and Club and years of production could vary.

I am more inclined to look at the differences in hulls. These are plastic and do deform under loads. Bows at varying widths / height at the tang point would result in differing bridle / forestay / rake outcomes.

BTW... we don't allow smoking in the metal shop.