I just wanted to add a public note thanking those many PPRuNes who sent kind messages of support, both publicly and via PM. I am wading through the PMs as we speak!
For the record, I have always been strongly opposed to drink-driving/flying. During 26 years of destructive drinking, I was tested many time (Australia was one of the first countries to get Random Breath Testing) and never was found to be over the limit. With the benefit of hindsight, I remain surprised that my efforts to control my drinking succeeded... The alcoholics amongst us will understand how desperate those efforts sometimes were
I am not a pilot (well... gliders, a long time ago) but I clearly understood that alcohol has an increasing effect with increasing cabin altitude. While still a student pilot, I was fortunate to hear a hair-raising story from a pair of pilots in a light aircraft after a heavy night who felt fine on the ground, but discovered they were seriously impaired at 10,000 feet. I am sure this information is part of the training for anyone who rises to ATPL level?
I suggest that the impaired judgement that is an inevitable result of many years of excessive alcohol consumption, is perhaps a more important reason to avoid alcohol on the flight deck than the well-understood affects on reaction times and concentration.
Knowing alcoholics as I do, I could suggest that the only rule that will work for alcoholics is "0" and "Always". If an alcoholic knows the limit is "none" and that he will be tested on every flight, he will find a way to not drink. Sadly, that "way" will probably include prescription medication.
If the aircraft carries a breathalyzer, and the Captain and First Office are required to test each other as part of their preparation for every flight, you won't have people affected by alcohol at the controls. Sadly, your alcoholic crew-members will probably be popping pills in the toilet.
I guess that we are all waiting for science to come up with a "Fitness Tester" that would detect no only chemical ingestion but also fatigue.
Many thanks all, for your kind words.