they get a lot of stick from us truck drivers but they do get it right some times - bless 'em 
was on the big orbital car park of london heading round to the M1, on my was to pboro - normally go m1/a421/a1 matrix signs warning of accident between 8&9 on M1 for quite a few miles on driving in the car park, anyway i remebered all the flak they get on here and thought iād chance it as 90% chance it was warning me about an accident that happened a week last thursday 
figured I could come off at junction 9 for Hemel take M10 across to the A1 if it turned out the matrix signs were telling the truth.
came up the M1 to hemel, signs saying queue after next junction, its an incline so couldnt see if there was actually a queue after junction so i bottled out and took juncton 9, and sure enough, my jaw hit the steering wheel, bugger me traffic was stacked nose to tail for as far as the eye could see just after the juncton.
so despite the flak they get on here some people at the HA seem to know what they are doing, and thankyou - you saved me a lot of bother, yes could of stayed on m25 and gone up the A1 that way but life is no fun if you dont take the occasional risk.
was it a major RTA or just a shunt 'n bump?
cheers
CC