It's easier to make combinations that satisfy conditions a and b using light yellow and dark red or blue, etc., ... but all the part about picking colors that "shift in accordance with the natural brightness" is nonsense. (I can pick colors that shift "opposite the natural brightness" which look just as good.)
Anyone wanting to really understand color should hit the books, or—if confined to the internet—should take a look at http://www.handprint.com/HP/WCL/wcolor.html and in particular this page: http://www.handprint.com/HP/WCL/color11.html