tis stupid.
they will have to make sure that everyone knows its changed or change all the national speed signs to say 50mph.
theres a road near my parents' house that i've always been able to get any car i've driven down it at 60mph despite the tight bend that occasionally has some flowers tied to a tree. the road is now all 40mph because of this corner, do people take much notice? no.
they would do better to remove stupid road signs and simplify the information presented to drivers and put warnings up for tight or sudden bends, teaching drivers interpret the information.
During the summer i was working as a contractor being sent round various schools in the UK and expected to get from coventry to the rhonda valley in wales for 9am, due to roadworks, a 3 hour drive, with a 50mph limit on most of those roads, would add an extra hour, impacting on various businesses that rely on deliveries in areas with no motorway network.