Hmm... I believe you should leave 20 mins before using a breathlyser so the readings are hardly accurate. Also, would he *remember* the readings after doing all that!
Interesting looking at the BAC for various countries here:
http://www.breathalyzer.co.uk/limits.htm
Presumably where it says US: 0.8/1 that is somewhat incorrect?
The UK's is 0.8 (BAC 0.16%) - this is still much lower than people realise. I hear a lot of people say it's "two pints" not realising the "two pint" rule-of-thumb (very bad and inaccurate in itself, of course) is based on weak ale (3%), not Stella which is likely to put you over the limit.
Personally I just have one shandy and know I'd be at more risk if I used mouthwash in the morning!
Gareth