I know that wax is dyed and I know that's reason why ptex changes color. But question was, if wax doesn't penetrate ptex for more then 800nm, how can ptex remains, lets say red, if it's about BP88, after stone grinding, which removes way more then 800nm of ptex? As I said, maybe real world is more then just looking through microscope, and while I agree most of servicemen have no scientific background, they still make skis faster, mostly with things and methods that aperantly shouldn't work, yet in tests it proves they actually do work in real life.
