now that is something I never would have considered, but it makes sense. The caffeine content of some of the beverages now is insanely high. It doesn't affect me at this point, I can have a cup of coffee and go right to sleep, but I think you have something there with the blood sugar. We've had more than one member have to pass off the transmitter to someone when they were feeling dizzy/weak. I agree on the later hour flight time, sun on it's way down, winds typically die down, and the field starts thinning out.