One glass of wine with dinner may or may not be a problem. Any amount of substance that rearranges your brain's chemical neurotransmitters taken on a daily basis will result in permanent physical adjustments in your brain. Whether or not that change results in detectable cognitive dysfunction is another matter and I believe varies with the individual depending on genetics and environmental factors. And maybe simply, how long have you been doing it?
Translate into English: yes, one glass of wine with dinner might mean you're an alcoholic for some individuals. For others, it might not, and never result in any impairment in the next day's functioning. Or at least in any degree of detectable impairment.
Now the question of whether there's a small undetectable impairment that might have contributed to the incident, now we're back to the spectrum of likelihood. No, we can never prove that your one glass of wine with dinner was a factor the next day when you augered in but neither can we prove that it wasn't. The truth is that many things impact our performance including age. When the impact of that one drink is less than the effect of simply being 60 with your slightly slower old brain, it would be more logical to deny anyone 60 years old a certification than to worry about someone who has a glass of wine with dinner.
The truth as I see it: these things are cumulative. You're going to decline with age. You're probably already declining with subclinical pre-pre-diabetes if you eat the U.S. diet, and there's always the effects of mood, fatigue, get-thereitis, and so on. Why add one more thing to the pile?
