That was the whole point. Driving is a very complicated task, moving at speeds much faster than the body can accomplish on its own. Thus, our brain puts some tasks on "auto-pilot" to focus attention on others. When driving we see what we expect to see. Part of why so many ppl run into stopped emergency vehicles on the shoulder is because when someone sees a vehicle with flashing lights facing the same way they are the brain assumes that the emergency vehicle is moving faster than the rest of traffic. Since ppl don't expect to see a stopped emergency vehicle they don't see it and they hit it. Experiments have found that if the police were to park their cars at an angle on the shoulder then almost no one would hit them because the brain would be forced out of "auto-pilot" and would have to process the situation. The same thing is true of accidents. Many accidents happen because someone did something we don't expect. Or because someone looked but didn't see any traffic so they pulled out. Because our brain knows that stop & yield signs are a specific size, shape & color it processes them on auto-pilot without actually seeing the sign.
The lady that hit my wifes C-Max gave a similar story. The Toyota that ran upon the median distracted her to the point on colliding with the C-Max. My wife when looking at the same situation slowed to a stop and only hit the vehicle in front of her after the lady behind her pushed the C-Max forward from the impact. Pre-Collision warning may have helped the ladies attention focus back to the stopped C-Max.
Edited by darrelld, 24 July 2014 - 01:27 PM.