isn't the yellow end of the spectrum easier on the eyes? i mean, if you are to say that blue is bad, hence the need for blue blockers- wouldn't the natural assumption be then that white (which is a combination of all colors of the spectrum and therefore have blue in it) would be bad as well.
my understanding is that yellow (to be more appropriate- "natural") light was chosen for that very reason. when HID's came out, they were annoying to some oncoming drivers but were more useful to the driver of the vehicle in question because of their HIGH INTENSITY. However, these wannabe white lights (i.e. PIAA) merely are colored white, do not offer any increase in discharge and therefore lumination, and so offer the driver no advantage and still serve to piss off everyone else.