We do a lot of motorway driving early on Saturday and Sunday mornings (on the way to dog shows). Mostly M3, M4, M25, M23, M1, M40. I would say almost every trip we get a totally spurious warning or speed limit from the orange matrix signs. Last Saturday on a deserted M4 at about 7AM it was "Caution 60 mph" then "Caution 40 mph" ... then nothing. Needless to say the motorway was totally clear, no evidence of there ever having been any kind of problem. Nothing on RDS. Another time we were in bright sunshine mid-afternoon and got "FOG" displayed?! Why do they display rubbish so often? Nobody seems to take any notice of them ... which is hardly surprising. The gantry signs on the M25 seem much more reliable ... lane closure warnings etc. are generally correct.