I agree with cutting caffeine out, mostly, for daily use. But we aren't talking about daily use here. I keep a small quantity of it, and psuedoephadrine, in my gear for times where I need mental clarity and energy for just an another hour or two. I understand, and accept, the potential short term risks. But adrenaline doesn't always last long enough, your body will only make so much before it stops. Then you crash.

Caffeine works if you don't overuse it. But just like an analgesic, antipyretic, antibiotic, or heavy duty pain meds, if you use it when you need it, it helps you. Saying "my body can keep me awake" is like saying "my body can keep me healthy" and completely ignoring the value of vaccines. We have technology. Those who abuse it are no greater fools than those who ignore it.