Here is my opinion on this subject.

I come out in the wee hours of the morning, and I have to merge into rush hour traffic. The traffic is moving upward of 45mph or faster. After I finally merge in, cars are passing me, upward of 50mph and close. Finally, I am in the traffic, and I move from a single lane road to a dual lane road with a middle turning lane. I take one of the full lanes. Cars are passing me upward of 50mph. When I approach a corner, and a car is waiting to make a left turn, the cars wait for me to pass, each and everytime. Sometimes from as far as a full block away. Also, cars pulling out of driveways, wait for me to pass. This is the respect I get for running strong flashlights up front.

I don't run this setup on bike trails, MUPs are anyplace where pedestrians and bikers are at. I run this setup in the balls out knock down drag out rush hour traffic. When those cars pass me at those speeds I imagine what would happen if one made contact with me. It would not be a good show, I tell you that. Now, as far as blinding lights on a bicycle, I think all bikers who are running strong lights, have them aimed downward toward the road, not up towards drivers eyes. Now I am only talking about bicycles on the road in dealing with cars, not other bikers and pedestrians. The bicyclists are only visible to cars for a second or two. IMO, that second or two is very, very important for the cyclists as far as being seen. I think we all know the result of not being seen by a fast moving car, and the car making contact with a rider on a bicycle, bad news. My lights strong enough up front that you can see the beam from the rear, and you know something is there. I said all this to say, I don't think strong lights on a bicycle are that much of a problem. Could be very annoying on the bike paths and MUPs, where only other bikers and pedestrians congregate. But, in the real world of fast moving traffic in the night, IMO, a full blown searchlight on a bicycle would not be too much. Again, just my opinion..

Here is how I have my lights aimed.. As you can see the beam is forward usually about 20 to 30 feet.