For a year or two, sometime back, I had an English gent for a Project Manager. Great guy, one of the best PMs I've worked with, and razor-sharp mind... one of the fastest learners I've known. Older than I was, he looked better, seemed to be in excellent shape, and played sports frequenly. Smoked like a chimney.

At one point he confided to me that he used to work for a brewery in the UK, and that he was in the habit of drinking 1-2 sixpacks of beer every night, sometimes more on the weekends. I never saw him hung over, or even looking tired... unlike the rest of us on the project.

I guess you can get used to anything. Though I think it would have made me unemployed in rather short order if I'd tried his routine, it obviously worked for him.