ETS:
Fwiw I think UK motorways will never work as intended (free flow of traffic over large distances) simply because there are far far far too many junctions and where they are few and far apart the ones there are are too overloaded and spill over the motorways so no win :_(
No better example…
Than J39, 40 and 41 of the M1. Three junctions serving Wakefield with the locals hopping on and off for a junction or two which in turn causes congestion for traffic that has no interest other than trying to pass through.