I wouldn’t give this advice since I learned thirst is messed up in many people but I actually follow this and I think it works well. I am a thirsty type, it seems.
So I guess people who have a well working thirst give this advice thinking everyone is like that. Or maybe the ones who aren’t hydrated enough themselves but think it’s the normal. I had no idea on high-carb that it’s not my optimal health…
Some people actually drink way too much water. Some of them dies. So it’s not impossible. I don’t know how hard is to flush out electrolytes so I don’t talk about that. Water has a fatal amount and I don’t know how but people is able to consume that by their own will sometimes. My body screams “it’s too much” so I am super thirsty, my throat is dry and still can’t drink (very rarely but happens when I do some cycling) but some people don’t work that way.
I am sure some people are super sensitive about electrolytes too. I don’t know how serious is this, I never gave these advice or warnings but I consider them valid in some cases. But it makes things so complicated, I am so glad I don’t need to worry about my water and salt… Or peeing in every 2 hours, well that would be awful (hydration is more important but still horribly unpleasant, I imagine).