since you asked, i very infrequently drink alcohol, and on the occasion i do, one or two beers/margaritas over the course of an afternoon and evening. My carry is secured beforehand, and won't be touched until the next day.
the discussion is bordering on the absurd given that even your example of 0.08 will have differing effects on different people based upon various physiological differences in liver function like alcohol dehydrogenase production, ethnic background, etc. that stuff even varies by day for the same individual and can change over the course of a lifetime. so, you are correct in that a number ofvfactors are subjective.
even the law is based upon arbitrary measures. the applicability (nullification?) of those measures/laws are what matters and requires judgement and consideration of a "gold standard" as i have been attempting to convey in the prior posts. geesh, even va law says you cannot drink while (concealed) carrying.
if you feel comfortable drinking a fifth and messing with a loaded gun, that's your business. if something bad happens and negatively impacts me or my loved ones, there will be issues. consequence for action. imo, one should not occur with the other. your opinion seems to differ - enjoy, you have that freedom to do so and responsibility for the consequences.
overall, the op asked for an opinion and it was given. i have no expectations for anyone to accept it. take it for what it is - an opinion based upon the paragraph description of a situation.
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And if Bruce Dickinson wants more cowbell, we should probably give him more cowbell!