But "flashing" doesn't mean strobe, correct? To my mind, "strobe" means the very fast flashing that can cause seizures and has no place on the streets, although I did have a red back light that had a weird strobing pattern as one of its presets.
By flashing I'm guessing you mean patterns that are between 1 and 2 flashes per second, correct? I don't see a problem with those if they're not blindingly shining into your eyes.