I'm a bit surprised that .08 BAC corresponds to 70% ability.
That means that in many cases, a good-but-legally-drunk driver will be vastly out-performing a terrible-but-sober driver.
I'm just glad my car will drive itself soon.
That means that in many cases, a good-but-legally-drunk driver will be vastly out-performing a terrible-but-sober driver.
I'm just glad my car will drive itself soon.
Not really. Drunk-driving is illegal due to increased reaction times, not decreased driving ability. You can be drunk and properly follow the traffic laws, but if you run into a situation that requires quick reflexes you're much more likely to not react quickly enough.
Whereas terrible drivers are generally terrible in other ways.
(We opt not to lean to the more permissive side because drivers who are drunk are indeed already responsible for a great deal of injury, loss of life, and damage)
Seriously, I can drive for fifteen minutes and see dozens of people who are driving too close together or committing some other sin. All those people who, just going into a corner, you see lighting off their brakes one after another - when all you, a little further back, have to do is roll your toes back a little to take some of the speed out.
Considering random breath tests don't seem to be that big of a thing, (I think - https://www.askthe.police.uk/content/Q723.htm - that they can't do truly random testing,) they're probably picking the people liable to be the worst examples anyway. Which I suspect is the most we can practically hope for at the moment.
for better or worse, it's not far off. imagine we could cross reference some street level CCTV (license plate, maybe gate and facial recognition) and "select driver_dl from trips where driving_ability < 0.7"; revoke licenses from those who can't drive well, consistently... to pay for it, maybe, we could just issue some DUI tickets where the car was parked in-front of a bar for a while and the driver appeared to walk unusually (dozens of violations per habitual drinker, ez). cross reference some phone/text and CC metadata to determine sociability and spending, maybe more, and you can get a pretty good certainty who's probably driving under the infuence and/or a poor driver, and take them off the road.
barely fiction (maybe not at all?), but it won't be hard forever and they won't need to "stop" many people in the sense that is hard to do, for much longer.
In the absence of usable public transit and a populace capable of bicycling, I guess we'll just have to wait for the self-driving cars...
I do agree with your general point though.
How do you know what percentage of ability corresponds to bad driving?
It is based on reaction time. So if you approach a stop light that turns red and you have a 70% score, you are taking approximately 30% longer to hit the car brakes.