I mean, as soon as the driver figures out the source of the flashing annoyance is just some geek bicyclist riding up ahead in a bike lane, do you really think that's going to keep him from taking his eyes off the road to remove the rest of the tomatoes from his hamburger? Or to keep her from taking her eyes off the road momentarily to get something from her handbag and lose concentration?
Most drivers consider a bicyclist, even in the bike lane, of sufficient interest to keep their tomatoes on as they pass. Please provide evidence that they do not. My only evidence is anecdotal. Most drivers I know worry when they pass that the cyclist may veer into their path and they are afraid of hitting them.