On the other hand, had he been an electronics tech who had to sort resistors by color code or deal with colored wires in low light situations, his difference might have become, not only apparent, but an actual handicap.
Exactly. If color is subjective, how could we all agree on how to sort out a blue wire. Or how could anyone say "Do you mean the light blue wire, or the dark blue wire?" When my mind "see's" the color I have labeled "Blue", it "see's" basically the same as everyone else's mind does for that color. Now your name for the blue color may be "H214x", but our minds still perceive the color as the same regardless of the label, unless you have some damage to your eyes or brain that would cause a color-sensing defect. If I were color blind it would not mean that a stop sign is not red just because I can't see it. Even with the other persons Indian color example, do you really think if a modern person were shown the black-soot and then the black-sky colors they would tell you the colors were identical? I imagine that this person would answer "black" to the question, "What color is this?", but I also believe that if this person viewed them side by side they would probably say that they are both black but maybe the one on the left is darker, and I'm sure that 99% of people polled would say the same. If this isn't color or shade recognition by some type of reflected waveform then what is it? I think we are all saying basically the same thing, but sometimes with this group you have to pull back far enough for everyone to agree on basic, generalized statements.