This is stupid for two reasons. Where there are static cameras they could be used as a warning before the camera so that drivers correct their speed. I assume the intention of traffic speeding reduction technology is to reduce speeding and not just handout more speeding tickets. The latter just antagonises drivers when the Police really need the public to be on their side.
Where there are mobile camera sites these digital traffic speed-warning devices can also when vehicles broke the speed limit and by how much, this would give the relevant Safety Camera Partnership a far better idea about where to put the mobile units and at what times etc.