In these days of rapid movement, when existence has become little more than a series of shocks of varying intensity, astonishment is the shortest-lived of all the emotions. The human brain has trained itself to elasticity and recovers its balance in the presence of the unforeseen with a speed almost miraculous. The man who says 'I am surprised!' really means 'I was surprised a moment ago, but now I have adjusted myself to the situation.' (The Little Warrior, P.G. Wodehouse)
Blonds, according to an Indian filmmaker, are more expressive: the shadows thrown by light stand out more clearly on their faces and bodies.
That seems to be true. Even dark hair on light skin distracts from the shadow play.
The question then is, why should it matter? What's so good about a fast read?
It seems to be true is that individuality takes longer to see. Pornography tends to favor blonds and light skin for speed of recognition.
Pornography shows us that speed of recognition works both ways: those doing the looking don't call upon their individuality just as the those seen don't express individuality.
Individuals should then prefer the dark haired, dark skin for the demand they make to stand back, reflect, and look deeply. Or they should prefer the light haired, light skinned so they can get better at resisting social conventions.
It really doesn't matter at all.