Well for one thing - we ARE a small target. Alot of drivers aren't just idiots. Would you say YOU are an idiot when you're driving your car? I know I'm not, AND I'm bike centric, and still don't spot the odd bike rider now and then. So apart from being a small target, there is another major issue often not considered. The background. Be conscious of the general background that is behind you as you ride along. Consider just how well you might be blending in. The fact that you exist, doesn't mean you're "seen". Of course this applies at night especially! Coming home from work, peek hr traffic - a driver ahead waits to pull out into the traffic. Consider what he is seeing as he looks down the road in your direction...mmm...what's behind you - a myriad array of headlights, maybe a shopping centre all lit up. You would be wise to consider yourself hidden within the sparkling, glaring, jittering lights. Effectively invisible to the regular cager, just trying to get home like you are. So, just be a little aware of the background and assume you might be lost in it, and ride accordingly. Even in broad daylight.