Hot Wings,
The trouble is you know when you're knackered. You don't feel the effects of a couple of glasses of wine but your reactions may be impaired.
I recall an experiment the RAF did some years ago. They put a Jag pilot into a simulator and threw the odd system failure/emergency at him. He coped well and landed the aircraft.
They then gave the same pilot a half or so of beer and flew exactly the same profile half an hour or so later. Result, crash and burn due to slow reflexes and muddled decision making. Alcahol and flying/driving definately don't mix.
The issue of fatigue is a separate one and not connected. Until the bean counters have less influence over flight safety issues such as being able to hire sufficient staff to be able to fly a full schedule without fatigue, the situation will not get better. The fact that some crew members choose to live well away from their base is also a factor in fatigue but, again, is a separate issue.
I really hope it will be resolved before the inevitable, but as the history of the industry has too sadly shown, the chances of this happening are very slim.