What's the speed limit? (update)

Back in October I blogged about the ridiculous speed controls on the A40 between Gypsy Corner and Savoy Circus. I note this weekend that the speed limit is still being advertised over the 400 or so yards of the average speed check as both 20mph and 30mph. A mixture of signs means that some motorists are sticking to 30mph, some to 20mph and some to somewhere in-between, with obvious resulting problems.

Is it too much to ask for some sense in the signing of speed limits, or is this another way of deliberately raising money through driver confusion? Either way the current situation is dangerous as drivers drive through the roadworks with one eye on their speedometer.