Motorists are used to seeing things on the road, standard things, and a flashing headlight is not one of them. Think about the percentage of people who ride their bike at night. You may do it on a regular basis, but you represent a smidgen of what is on the road.

I commuted for three years on graves, and only used blinkies in the rear, and red at that. When people discovered I was riding my bike at 4:00 a.m. in the winter, or 10 p.m. in the summer, they asked how I made myself visible. 95% of them said my white front blinkie is worse than a steady beam. A decent headlamp (Magicshine, MiNewt 600) is all you need to be seen. If a motorist doesn't see that, they are not going to see one flashing.

Your experience may vary, but on a large scale, flashing whites are not good for night-blind drivers. Again, my personal experience.

It is remarkable how two conclusions can be reached form the same scenario. Not saying you are wrong, just noting that the difference is stark.