PETER Heaton-Jones raised some interesting points in his column concerning speed restrictions on two dual carriageways in Swindon.

I too was annoyed when the limit was cut to 40mph between the Mannington and Bridgemead roundabouts, but I timed the stretch between Barnfield and the next traffic lights to see if it was worth bothering about; it took 50 seconds at 40mph, so you would probably save about ten seconds if you travelled at 60mph.

I suppose the traffic people were merely making the whole of Great Western Way the same speed limit.

Peter calls the Northern Orbital road hideous, but he doesn't say why. I avoid it whenever I can, simply because of the number of traffic lights.

My daughter says that "if you cop one, you cop the lot," and I think she is right.

Many years ago in Slough there used to be a similar system and the official line said that the lights would remain at green if you travelled at 25mph. It certainly seemed to work very well indeed and I am wondering if something like it could be tried here. Can anyone help?

GORDON CRABBE

Westlea