Hi Paul,
Have only just caught up, so sorry to see what has happened.
Here is a little bit of medical science for you. Part of the reason why accidents happen can be attributed to the fact that our brains take time to process the images that we see and the sounds that we hear. People will often say that we don't live in the past or in the furure, rather we live in the present. That is true to a point, but for what we see and hear, we are indeed functioning in the past. It may not sound like a long time, but everything that we see and hear actually happened, in round figures, 1/3 of a second ago. When travelling in a car or riding a bike, the brake lights on the vehicle in front will actually be on for 1/3 of a second before you realise it, and that can be all it takes depending upon the speed in which you are travelling and the distance between for contact to be made. Think of it as a propogation delay, a term used when describing the time taken for electronic logic gates to process information.
So based upon the speed that you were doing initially, between the brake lights on the vehicle in front being seen by you to be on, you have actually travelled forward some 5 metres during that 1/3 of a second. When you add the necessary reaction time of applying the brake, the 5 metres that you lost initially can and did make a real difference.
It is like when you have a fall whilst out bike riding. I know from experience that by the time you realise what is going to happen, it is quite often all too late. Then you think to yourself, how did that happen. The processing delay that we all live with in situations like that where every fraction of a second and every millimetre count, then make all the difference.
Ron.