Yes, you have to make quick calculations in your head on a moment's notice when working as an AA, and no, you WON'T have "scratch paper" there for you to write down conversion factors and proportions or whatever the hell else your pea-brain needs to process information that shouldn't require any effort from a real anesthetist. Okay, maybe "pea-brain" is a bit harsh (though probably not), but the fact remains that you just don't have the brains necessary to be an anesthetist. I sure as hell don't want someone like you responsible for my anesthetic care, regardless of whether I'm having a simple outpatient procedure done or a heart transplant.
You scored well on the verbal portion of the GRE, so why don't you look into a career as a writer? You won't make as much money as you would as an AA, but you'll just have to take the cards you've been dealt.
At least you won't kill an innocent patient whose only mistake was getting YOU assigned to their case.