I had an interesting conversation with a cabbie this morning.

He was telling me about hsi experiences being caught be various locations of temporary roadside (i.e. non-birdcage devices) around Hong Kong island. I was especially interested to hear his comments about LIDAR, because it offers so little advanced warning.

Firstly, it seems that locations almost always use the same kind of equipment, despite their having both multanova tripods and LIDAR guns. That means that they carefully plan each location based on traffic patterns, angle and elevation, availability of space, and availability of a suitable traffic stop location. Time and again, they will return to the same spot, set up the same equipment in the same way, with the same traffic stop arrangement, etc.

Secondly, multanova tripods are as likely to involve a traffic stop as not. LIDAR very rarely involves a camera flash and is usually associated with a traffic stop.

If they are set up to do a traffic stop and have not taken the car's photo, there is very little concrete proof. If the car is not stopped, they will probably not bother to come after the driver. Also, in some cases, not all possible exits from the road are attended.

So hypothetically speaking, if a driver knows the roads and knows he has been hit, what would stop him abruptly but safely turning off into a minor road, or maybe backing up a few metres on a deserted single carriageway, or even just parking and leaving the vehicle?