Dixie wrote:
I was waiting to cross the A140 near Coddenham and notice a guy with a (what looked like a video camera) hiding behind a road sign. He was pointing the camera up the road towards a speed camera.

I drive past that camera most days. I'd love to know what he was doing too. I can't find the figures now, but the accident rate went up after the camera was installed, although the number of KSI dropped. They remodelled the junction around the same time so it's hard to know the true effect of the camera or the engineering.
Maybe it was someone gathering data to try to determine why there are so many accidents. The main reason is fairly obvious if you use the road enough. It is a steep (for Suffolk!) downhill stretch on a 50mph DC and it is really hard maintaining 50 whilst watching for stuff pulling out at the crossroad. People don't give themselves enough space and you can't be sure if vehicles are braking because they are turning off or just slowing for the camera until immediately before the junction.
Be careful if you go up the hill northbound on the other carriageway before the Highwayman pub as it's a favourite haunt of the scamera van.