Even right now, if you try to swallow saliva multiple times as fast as you can, consecutively; you will hit a "bottleneck" :)
Oesophagus, operates on a rhythm, of which is initiated by the back of your tongue (where tonsils hit)
But, oesophagus, having mind of its own (involuntary); does not accept initiated rhythm, if it's "out of timing"
This "timing" is dictated by the way muscle contract and relax as they push saliva you just swallowed down into your tummy. Nasty yet brilliant ain't it?
Ah. My own sense of thirst is completely missing, so I almost never enjoy water. I just chug it like I’m doing a chore, so I tend to drink as much as I can put down without running out of oxygen or giving myself the runs.
I can drink off a liter at a time if I choose, but I don’t because that much water does actually reach the other end of the tube before getting absorbed.
So for full absorption I usually do half a liter at a go, ideally a few times a day. It’s hard to remember to though because, like I said, no thirst.