never understood the facination with camelbacks
I'll field this one- it's because drinking from bottles covered in crap is rubbish. Carry more, in comfort, and cleanly, without weighing down your bike, or ever losing a bottle. What's hard to understand?
The thing about riding with the minimum of kit, is that sometimes it turns out not to be the minimum. You run short of water, or get one more puncture than you can deal with, or it rains and you have no jacket, or it doesn't rain and you have nowhere to put your jacket... Camelbaks remove a lot of the ways that rides go wrong. Random passing Northwinds with camelbaks fix problems for people who've come out without kit they later want.
Drinking on a ride isn't just about avoiding negative performance issues from dehydration- it's largely about not being thirsty. Hands up everyone here who only eats when they absolutely need to, rather than when they want to? Why drink differently?