The brakelight is a fairly primitive tool, given the complexity of today’s road movements. Today’s invention attempts to smooth out the kind of jumpy driving which causes delays and accidents.
As each car brakes, it sends a radio message. Using GPS, only cars which are behind and heading in the same direction interpret this message. This signal encodes information about the duration and sharpness of the current braking manoeuvres ahead.
If a car is told that several vehicles travelling close together on the road ahead have all just decelerated hard then that car will extract a clear interpretation and issue its driver some kind of audible warning. If they have applied their brakes, but not slowed, it may indicate ice or oil on the surface.
If however, a chain of cars up front is repeatedly just brushing their brakes (because eg they are driving too close in the wrong gear) then the following car will issue its driver with a message to say “poor anticipation but little actual deceleration ahead.”
In this way, information about the ensemble behaviour of vehicles ahead is condensed into a more meaningful summary than a driver can derive from seeing the brake lights of only the car in front.
NB at no point am I suggesting that the car has its braking or steering taken over by some magical autopilot in a weird, fuel-saving, tail-gating, road train thing.
Where will the fun be in that, when I have saved for my long-awaited 911 😉 ?