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?
I too had dirty thoughts when I read the title. My father had alzheimers and the inability to swallow was the point were the disease had progressed to where there was no real quality of life you could point to at all.
You may want to look into a condition called EoE also known as Eosinophilic esophagitis. If that's the problem, you'll certainly want to see your doctor.
Swallowing requires coordination of a lot of different muscles. Do you mean that you can’t get the swallowing process to start or that you swallow and food doesn’t go down all the way?
I had a lot of problems with the latter when I was sick with undiagnosed celiac and later developing type 1 diabetes. I’d swallow fine, but it would feel like the food was stuck in my sternum and it was very miserable. They couldn’t find anything physically wrong with my esophagus at the time. My interpretation was the esophagus was inflamed from acid reflux and thus narrowed.