Traffic lights cause traffic jams. This was abundantly clear last Thursday and Friday when the failure of all the lights in and around Frideswide Square, Oxford, proved that they were unnecessary in the first place.

Though no less heavy than usual, traffic passed easily through this ludicrously complicated junction. The long queues that generally stretch throughout the day along Botley Road and Hythe Bridge Street completely vanished.

Taxi drivers and bus drivers gave three cheers. I heard them.

I negotiated the junction six or seven times, on foot, on my bike and at the wheel of my car. There were no problems; I never felt at risk; all road users showed proper concern for each other.

The same thing happened a couple of years ago when the lights broke. It happens when traffic lights are switched off in very many locations: Google the words ‘traffic lights switched off’ and read, if you don’t believe me.

And yet the traffic engineers insist that there should be more and more lights. It is a strange obsession with them.

Their political masters should tell them to desist — or we should change their political masters.