Hence you get what were once (dons petrolhead hat) "interesting" roads at the NSL dumbed down to 40mph to cater for the incompetent, drunk and distracted. This makes them incredibly dull to drive, although if people observe the limits, they should be safer for other road users, even though that probably wasn't the main reason.
I don't know the 13 bends of death, but the A346 from Swindon to Marlborough has a reputation for carnage. It's a mostly straight Roman road with lots of deep hidden dips. Despite the flashing LED signs, I still frequently see people overtaking when there is no way they can see oncoming traffic.