Human Factors?
Has any research been done on how quickly a driver who is reading or otherwise engaged firstly react to a warning, disengage from the book, assess the situation, then take the correct action? I reckon that will be several seconds and as 30mph = 14 metres a second that is quite away down the road. At 70mph I don't see humans being able to do anything in time unless they happen to be a part time F1 driver. Perhaps future driving tests will have a section on distraction reaction. If you pass you get a super-licence and can have an autonomous car. If you fail its back to the 2CV.