This idea is superbly silly, but slightly interesting, more for its lack of success than its ability to revolutionise how we see the world. It is, of course, entirely redundant - since many more useful ways of representing time exist. At its core is the idea of giving an instant impression of how far through the minute, hour, day, month, year and so on we have progressed. Of course, analogue watches manage to give an instant impression of the time in much the same way, which I’m sure explains their continuing popularity with anyone over the age of fifteen, or who is not stuck in the 1980s. Unlike this attempt, it is also possible to read them accurately (the better ones anyway), quickly, and without getting a headache.
The most interesting question is why this rather colourful display fails. I think its because (even if you realise that the spectrum “begins” with purple) the brain has to think far too hard about where the scale in each ring begins and ends. The colours themselves have no particular meaning to the brain, and do not even move from dark to light, but rather from dark to light to dark again. As a result, by the time the brain has worked out what time the clock is trying to represent, the eye has probably moved to that rather handy digital representation of the time provided at the bottom of the display.
Unfortunately, like internet time, the fad that never was, “Colhour” (which made no sense to me until I remembered the shortage of ‘u’ moveable type on the other side of the Atlantic) is an idea that seems to take itself altogether too seriously.