Originally Posted by chipseal
This is because when a distracted operator does a quick scan ahead, he processes the vehicle ahead of him as traveling at a similar speed to his own- That is, he does not look long enough to notice the closing speed.
Exactly. This is why a cyclist will be identified as an issue needing attention before a motor vehicle traveling the same speed would be. This is even more true if the cyclist prefers to wear tacky hi-vis or white socks which will immediately distinguish him from a motor cycle.
While speed diferential is certainly a factor, it seems to me that most rear enders happen to vehicles that are either making a rapid stop, or are already at a complete stop. Driving in a manner that reduces these two situations will reduce the chance of being hit from behind, car or bike.