Well I don't agree at all with any of the above posters. I drive at least 12000 miles per annum on our motorways and I'm an extremely frequent user of the smart motorways around both Bristol and Birmingham, and, compared with the pre-smart days, my passages through these areas have been much eased. Yes there's massive disruption that goes on for years via lengthy roadworks as the new system is put in place, but even in those roadworks the traffic flows pretty well most of the time thanks to the average-speed cameras. On the smart motorways the variable speed limits, operated by computerised camera systems that monitor flow and relay the recommended limits to the overhead gantries, ensure that everyone travels at an appropriate speed so that bunching is avoided. There are yellow speed cameras typically on every other gantry, at the side, not overhead, and they are well-recognised and the limits are generally obeyed. Of course, breakdowns or accidents can still cause congestion, as has always been the case, but bunching-congestion, a routine horror on busy non-smart motorways, has been much-reduced. So I'm a bit of a fan. Everybody knows that simply widening motorways just doesn't work, as anyone who has to endure Death Valley on the M60 would tell you.