PS: Getting back on topic, if anyone wants to know what the police were doing on the Mountain Road with a speed gun I can tell you.
I asked a traffic cop today and he showed me a new laser gun they've bought and officers have been testing it out.
He said from time to time you will see officers with speed guns in destricted zones to check the speeds of commerical vehicles, such as HGV and lorries which are subject to speed restrictions by their size and weight.
PPS: The new laser gun is very light, very accurate, and can pin-point individual cars in a line of traffic.