[quote=harinezumikouken]
Well, it's rumored that a beer or two can help lower your blood pressure and relax you enough to help increase focus. And though temporary, the chemicals in tobacco smoke has bronchial dilators that can open up your lungs and help you to intake more oxygen.
[/quote]

That seemingly defies logic. If you're more relaxed, it would be reasonable to me that you're less focused if anything. I guess that is why it's a rumor.