I think the traffic Amazon would be worried about is human drivers, not other drones. AFAIK, Google's driverless cars have been in 14 documented accidents and a

I think the traffic Amazon would be worried about is human drivers, not other drones. AFAIK, Google's driverless cars have been in 14 documented accidents and all 14 were the fault of human drivers (including one incident of a human driving the Google car). Machines may be better drivers than humans.