Here is a blood alcohol calculator in excel - click the link and if you have Excel on your machine, it should open. Otherwise right-click the link, and save as:
bac.xls
It is pretty useful for all crew (and SLF) if you're on a trip because even if you are a little dis-orientated from time zone changes, it'll give you a good calculation of bac without having to rely on judgment. Remember that the graph is % blood alcohol, which is not the UK ** mg of alcohol per 100ml of blood.
Playing with the calculator, I can see how the ".. hours bottle to throttle" fits the reality of a 0.02% alcohol limit. For a 70kg person (since weight makes a difference):
Couple of beers = 8 hours
Bottle of wine = 12 hours
2 bottles of wine = 24 hours
For a 105kg person (since weight makes a difference):
Bottle of wine = 8 hours
2 bottles of wine = 16 hours
crate of beer @ 3/hr over 8 hours = 24 hours and probably violently ill