I thought that this was a dual purpose test to evaluate both monitor and color profile, as well as color perception and acuity. Obviously, without a decent display, no eyes are going to be able to discriminate between similar shades, but that is part of the integrated system we use every day and are testing here. Of course, color perception is based on many factors, but I don't see how distinguishing subtle differences in colors could not be a worthwhile skill to evaluate.