Steve:
Me: What you like to think is the foundation of your chanty narrative.
You: I'm personally happy with the idea of 'proto-chanties'.

Yes.you.are. And your personal happiness is not pre-1842AD anything.

For scale: I suspect the proto-chanty concept is younger than Mudcat. The nautical fife is older than vowels and spaces between words.

PS Standing question: I've only word searched Seamen's Manual, not read it proper. Fwiw, only hit from 'the list' was "jack-screw" (with the hyphen.)