Yes, because the systems had failed and were giving them the wrong info. Bit of both, probably like the german train crash will turn out. But if an aircraft has trouble coping with ice crystals, how will the car deal with dirty sensors?
One of our roads has had the limit dropped to 60 from 80 to give drivers more time to respond to the roos. A stationary roo will leap out in front of you with no warning and if you aren't slowing down for what looks like a boulder right on the edge of the road, you could be in for a nasty surprise.
