Wayne, The remaining bulb should not shone any brighter than usual as they are are connected in parallel. Therefore the current draw will be the the same as before in that bulb and hence the same brightness. What I suspect is that these cabs are really just the outcome of cheap repairs. After a little prang, these guys go to cheap shop for alternative surgery and this leaves the car with glued parts or immitation stuff. Of course the repair does not include headlight adjustment and so you get the irritating high beam that is actually the low beam. :argue:
What to do..... either go faster and get another car to block the light or let that guy overtake you....
Cheers