Good point Stevie but I'm not quite sure what would be worse in a situation where you are gun handling:
-being tired, unfocused and risking making a common sense mistake because you werent alert and handling properly.
-being so wired up on caffeine that you are over-stimulated and accidentally jerk a trigger or whatever else might happen when you are jittery and going turbo speed. Plus I feel THIS would drastically alter your accuracy versus being tired.
When I hit the range, I try to be right in the middle!