Remember that blood alcohol content was started by lawyer getting folk off when a cop saw them driving erratic and smelled alcohol on them. What we would call using common sense.
How ever we have a safe formual for driving. One beverage per hour and ya golden to drive. Its the law because morons keep getting drunk and killing folks. Instead of acting responsible.
I wonder how MADD would respond if they were contacted. They were the ones who got the ball rolling and the crack down on DWI.
Why its not as simple as one drink per hour with a glass of high quality H2O in between for many folks I dont know.

I have no faith in human perfectability. I think that human exertion will have no appreciable effect upon humanity. Man is now only more active - not more happy - nor more wise, than he was 6000 years ago. Edgar Allan Poe