Disagree. That's what you are told is true.
30 straight years of drinking, no tickets, no stops, no traffic violations, no accidents. Not even near misses. If you were following me you would never even know I'd been drinking, and I'm not talking a few beers, I'm talking about times just like last Saturday night and a boatload of margaritas.
Sorry, there are people, lots of people, who can drink and drive. Unfortunately, one of us could get caught by a DUI road black even though no one is in any danger from us. They have road blocks for the sole reason of catching people they wouldn't by observing them. The people who can drink and drive. They do that not to save lives, but to increase the city coffers.
Certainly there are people who cannot drink and drive. I've seen them. They are the ones you see on TV trying to pass sobriety tests, or the ones you hear about who have had multiple DUI convictions. They are not everyone.