The post reads a little like a troll but anyways...
Your brain actually processes a lot more information around luminosity than it does about colour. In a similar analogy, its why somethings are photographed in infrared or using gamma rays and x-rays, sure you can't see those but by mapping it back to a visible spectrum it shows you something that wasn't visible otherwise. B&W photography presents basic form, pattern and luminous constructs of a scene that you can't see clearly when its masked by colour.
Just because your brain "registers" colour it says nothing about what it conveys to, or interprets from it.
A little harsh, but honest, is if you've made the original statement in any seriousness, what you are saying is that you have no clue about the characteristics of photographic imagery at all, let alone B&W.