Salt water?
Please tell me if I'm wrong in this assumption.
If you're hydrating properly (1/2 gallon+ of water a day, every day), you're drowning out your electrolytes throughout the day (I experienced the worst of this on a ride once after drinking over a gallon the day prior and it was awful). Then, you're sweating out even more of your sodium on your ride, making the electrolyte situation worse. So, if you're a frequent water drinker AND you sweat out lots of salt, shouldn't you be dropping a decent amount of salt in your water bottles to keep the sodium levels up?