BUT, bikes and more importantly their riders don't have to be as hard to see as a lot of riders choose to make them.
In no way with the possible exception of bike night ninjas am I saying that excuses people who don't keep their head up and actually look around closely when they are driving and watch for bikes.
What I am saying is that the guy wearing drab colored clothes on a drab colored bike needs to read that sign as well. In my opinion most bikes should come painted in a bright stand out florescent color preferably with reflective paint that turns the entire bikes frame into a giant reflector. The rider can also do something about the clothes he/she chooses to wear. If the bright colored spandex outfits aren't for you then a $12 bright yellow or orange reflective vest is an excellent investment. Also check the hunting section of the sporting goods section, hunters safety orange hats, coats, sweatshirts, T-shirts, vests, back-packs, fanny packs, . . . etc. . . they all make good cycling stuff too for high visibility so people are much more likely to see you.