cmaha76:Let me start by saying that I would never drink then dive. That's just me. Just to play devils advocate, wouldn't a couple of cups of coffee in the morning be just as bad as drinking a bottle of beer as far as dehydration goes?
If we were only talking about dehydration, there would be some truth there. We have to recognize the danger of dehydration and act accordingly. Thus, if I have a few drinks the night before a dive, I make sure to hydrate. If I drink coffee before a dive, I make sure I am also drinking other liquids.
But we are not just talking about dehydration.
If we are talking just before a dive, there is a world of difference between the morning coffee and the morning beer. You need to exercise good judgment throughout a dive, and you want to avoid anything that will impair that.
As someone who has made a number of speeches in settings where there was alcohol available before, I limit my drinking to next to nothing if I am going to be speaking. Even a little will keep me from being my best.