It’s not really a problem, since she sees most colours clearly and only has trouble with a few mixed shades, such as turquoise or some brownish reds and greens. We sometimes argue about the colour of shirts or shoes, but she usually has no problems matching her clothes.

Your article shows how ‘colour blindness’ is a somewhat misleading term, as it suggests a black or white situation (no pun intended), in which you either are or aren’t, whereas in fact colour vision is much more complex, with many shades in between. In a way this also applys to the ‘disability’ question. In my opinion, complete monochromacy obviously is a disability, while mild red-green deficiency clearly isn’t, but there is a broad spectrum of intermediary cases.