I HAVE to have caffeine Saturday morning or I wouldn't stay awake in the stand! It's our opening day of firearms season and I won't sleep worth a crap Friday night, and as a tradition we all get together at mom and dad's between 4:30 and 5:00 for a big breakfast! So...that being said, caffeine in the stand is pretty essential for me!
I will say this, when I shot in indoor archery leagues, I had to avoid caffeine like the plague. With that kind of accuracy and consistancy required, there was a noticable difference (for the worse) in my groups if I drank coffee or Mtn. Dew before I shot my 60 arrows.
But...as some of them have said, the caffiene shakes PALE in comparison to the way I shake when a deer is in front of me anyway!!