This guy is not being charged with being drunk. Someone in an earlier post said clearly he's been changed with 'operating an aircraft under the influence of alcohol'. Not the same thing at all.
The mouthwash excuse is I'm afraid so much rubbish, been tried under Road Traffic law in the UK, failed. There would be no effect from mouth wash on an evidencial breath test machine 20 minutes after you had used the mouth wash (thats why you are asked in the UK by Police if you have used mouthwash and are required to take a breath test)
Other excuses used which failed are exessive eating of pickled onions and use of ciggaretts.
I assume the US system of Justice is much the same as the UK, in that before charging someone you need to have sufficent evidence to support that charge. In the UK, that would mean you had would have provided a specimin of breath on a calibrated evidenial breath test machine at a Police station. This would then produce a print out of the blood alcohol concentration, which is then the evidence used in court.
I agree there seems to be a problem with the press making a distinction between being drunk (assuming this guy was not) and having more alcohol in his blood than whatever the US use as a prescribed limit. However the fact he wasn't drunk is not the issue.
By the way 4PON4PIN, I wouldn't try 2 pints on the way home, as you may well find you are substantialy more over the limit than you think. The Home Office advice is 2.5 units of alcohol will put you over the drink drive limit, thats 2.5 half pints!