Where Does the Glare Come From?
Recommendations

The present report investigates and examines the various sources of glare in the US nighttime traffic environment. In the context of this investigation, several solutions suggest themselves to reduce the glare that currently makes driving at night in the US a driver-hostile experience,as well as to improve seeing. Here are some suggested courses of action, supported by the science and discussion in the present report.

1. Lower the allowable glare intensities for low beam head lamps, particularly at (H,V) and (0.5U,3.5L), because the currently allowable levels are too high.
2. Raise the allowable high beam intensity at (H,V)to match the European and Japanese maximum of 140,000 cd (nominal at 12.8V), because more intense high beams will increase visual performance in situations warranting high beam use, and will discourage misuse of high beams in situations warranting low beam use. (we can only hope)
3. Establish stringent requirements for colorimetric, projected-area, mounting and photometric performance of original-equipment and aftermarket auxiliary lamps, because such lamps are currently a significant and uncontrolled source of glare.
4. Lower the degree to which “white ”illumination may tend towards blue, because this will reduce the production of inherently-glaring blue light and will also reduce the motivation for individuals to attempt to attain a “blue ”appearance with halogen headlamps.
5. Require automatic aim compensators (dynamic headlamp levelling) with HID and high-flux halogen headlamps, because such headlamps create severe glare with vehicle attitude changes.
6. Raise the stringency of MVSS 101 requirements for the high beam telltale so that the words “BRIGHT”or “HIGH BEAM”appear with (or instead of) the ISO symbol, because many drivers do not notice or recognize the ISO symbol. (idiots )
7. Raise the stringency of headlamp lens marking requirements so that headlamp assemblies intended for gas discharge sources are clearly differentiated from those intended for halogen sources, because current regulations allow misinstallations to go undetected.

Here's the link to the PDF docuemnt (as if anybody cares): http://www.pergolesi.demon.co.uk/dastern/wdtgcf.pdf