. . . I can not believe that it is safer to have a flashing light as opposed to a static one.
. . . Like I say I think they are dangerous.
. . . You vision is drawn to them and concentration compromised.
I'm not a "Proper" cyclist, but I do cycle sometimes, as well as riding a Motorcycle, and I'm a Car Driver.
Those flashing lights are now quite legal, but they didn't used to be. It was found that vehicle drivers didn't notice the small, often dimly-lit standard lights, and statistics show many accidents were caused, both from front and rear, so the law was changed to allow flashing lights.
The fact that the three of you notice them prove that they work, and that people do notice them. I do not see how your concentration can be compromised if you are a competent driver, as you take notice of the lights, think "bike", and carry on driving hopefully safely. I drive a lot after dark, and it's very rare bicycle lights bother me. It's generally some very bright headlamps on some modern vehicles that tend to be a little over-the-top.
Bicycle lights on well-lit roads are not used to see where you are riding. They are only used to let other people know they your there. They are used and worn for self-preservation by cyclists. After all they do not have a wall of steel around them or air-bags, so are very vulnerable to even low-speed prangs.
I personally ride after dark with large-diameter fixed lights, which are bright, but after a close rear-end "incident" in town, I'm gonna buy an extra flashing one for the rear as well. Like many Motorcyclists already know, a lot of vehicle drivers do not look out for bicycles or motorcycles, and will pull out in front of them, without looking properly.
