Many thanks for your reply.  

But did they actually see things in different way, because of differences in their eyesight, or in their brains?    That's why I think it's relevant to Poser, because some Poser textures drastically differ from others, but in technique, not quality  (i.e. they seem to get the same resul, in totally different ways.   Just as those painters did a great impression of water, in totally different ways, Poser artists choose fairly radically different ways to portray people, but the best end up deceiving the eye just as well, regardless of technique.