I do think that surprising because I really think English Law is an ass. So it must obviously get more right than I usually credit it for.

Those poor kids! Strapped into cars and fussed over by Mother Goose as they are transported from one ultra-safe environment to another. I walked to school in all weathers (just over half a mile) from the age of 5 but for a couple of years I had to go with the Big Girl Next Door. She was 7. Kids these days have no chance to climb trees, get a "bootful" from the pond, cope with falling over, learn to cross the road or not talk to that funny-looking man. I am extremely grateful I was born in 1942 and not 1992 (say).

(st d) The 70 limit isn't archaic and certainly not draconian. You are taking things too literally. It's there to stop people doing much over 85. A higher limit would lead to everyone going faster still and there'd be a few more accidents. 70 is fast enough, anyway. 50 miles at 70 mph takes 43 minutes, at 85 mph 35 minutes, but on the M25 several hours. You just like driving fast; so do I. But it's a bit naughty, and a bit pointless. :-)

[st d] I thought you had your tongue well and truly planted in your cheek when you wrote your original motorway exposé. Thanks for your clarification - it was your statement "I drive at about 90 most of teh time, occasionally creeping up to about 110 for brief periods or dropping to 70 if the road is clear." that led to my interpretation. In my judgement there is nothing wrong with speed itself, it's where and how and by whom it is used. These days I tend to treat everyone else on the road as incompetent, the idea being to keep alert to the fact that I am controlling a missile of significant mass and an error made by someone else could lead to an early demise - mine.
Of course we are all good drivers, of course we all have superb reactions and car control skills. Naturally all our cars are all in tip-top condition and handle like an F1 top ten machine. If you believe all that then you're a cylinder short of a block. Some of this comes from bitter experience and these days I stick to the speed limit (I cannot afford to get caught) even though there are places where said limits are really silly. Don't get me wrong, I was no angel in my younger days, I'm just thankful still to be here.
By the way, give me a bullet with wheels that will handle, a winding road and no traffic (ha!) and I'll be in seventh heaven. ;-)

[Dujon] That would be Lincolnshire (on England's east coast) then, which has one of the highest rates of road deaths in the country. Everyone who likes going fast, especially the motorcyclists, make that mistake. When I was a reporter, I attended so many inquests into the deaths of people who make exactly the same mistake, and over-cook it on corners just as a tractor, or a pensioner, pulls out of a farm gateway. If you're going to speed, please do it on motorways.