I think that, in considering the whole question of color rendering of films, and color matching generally, we can completely overlook our individual differences in color vision. I've been told by an optomotrist that it's quite likely (though hard to prove!) we each perceive colors slightly differently, which maybe why some think Kodachrome is an exact match for nature, while others prefer the Velvia-style rendering. Certainly there are recognised tests for color vision, which are used for staff in businesses like fabric dyeing and printing.