This is why I like to wear a retroreflective vest. The light returning back to the driver is directly proportional to the light they shine at me; they high-beam me, I high beam them back (I have had many cars switch to low beams when they get near me, it really works!). My headlights serve only as a back-up in case their lights are not yet shining at me, and, just like with car headlights, all of my LEDs point towards the ground and never shine directly at the driver.