-Yup, the affected population is so small I don't bother suggesting to websites and software publishers that they may want to adapt their colour schemes anymore

Kudos to my employer, though - after some discussion, I was given a small budget and our SCADA GUI frontends now sport colour palettes optimized for deuteranopes, protanopes and tritanopes.

We've got a couple of very grateful feedbacks - and, unsurprisingly, quite a bunch of 'Gee, did you have some colorblind sod do your GUIs? My display looks like a Grateful Dead cover!' from people who've inadvertently messed with accessibility settings...