An apology, as promised. I've spent the evening ploughing through the selected works of forgotten ABers like R1Geezer, Thatcherite, PetitAnglais, ZedBloke, MoonRocker and even Egara_Flegin, a poor backward wee mite who lived only a day before being suspended like the rest. And I couldn't find the post I thought I'd read at all (it wasn't about motorways, but you seem rather cross with people who don't drive fast enough). So for practical purposes it never happened and I misremembered it.
I did find a post along the way by someone called RedGrant, asking how the Romans counted big figures, which I will now answer in case he happens to be around. The very late Romans used all sort of letters: B=300, E=250, F=40, G=400, H=200, K=250, N=90, P=400, Q=500, R=80, S=7 or 70, T=160, Y=150, Z=2,000.
https://www.funtrivia.com/askft/Question47602.html
I hope that cheers you up. I am now light of heart, my guilty soul purged!