doggonetired, I am not a statistician either and I think your comments may be right but I think what Snooky is getting at is that most of the time there isn't a problem but you only need to throw in some extra "random" event (such as an aircraft malfunction) and the potential for a catastrophe is much greater.
I accept that we cannot base everything that we do on the worst happening but, as a pilot, I do know (from hard experience) that when you are getting low on fuel one's ability to make rational reasoned decisions tends to decrease.
At a much more fundamental level we have to ask what the purpose of business is? If the answer to that question is just to maximise profit (for example by carrying less fuel and "saving" money) then we are surely ignoring the bigger picture. For example, what is the cost to the "nation" if passengers do not arrive at their chosen destination? Some might say, so what? But I would say that what goes around (pardon the pun!) comes around.
We need to take a much more "holistic" view - for example, it might be argued that if ATC is subject to more "stress" because of a couple of aircraft crying a bit low on fuel that they might be more prone to error and miss something else which is more important.
Finally, it concerns me as pilot (and a passenger) that many of us are constantly working in "overload" - we can do this "occasionally" when necessary but if it's every day, then eventually something will give and there will be a catastrophe.
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