Neither of those tips are true unfortunately. It's the...

Neither of those tips are true unfortunately. It's the metabolites of Alcohol that cause the hangover, drink too much and your liver simply can't process enough (good trick is to work out where that point is for you).

Hyperventilating doesn't blow the alcohol out of your bloodstream (unfortunately) so any ventilation (ie taking a deep breath in before blowing) will simply "reset" things. You're sorta right that given residual volumes and other technical stuff that you might just change things by a tiny fraction but if you were that close to the limit then I'd suggest you'd have a better chance of trying to fart into their machine and claim mental illness than getting away with it.