John, you wrote, in part: "There's nothing about sight that makes you look at an 's'
with a mark under it and immediately go "ah yes, that's the 'sh' sound,
as in English 'ship"! You learn that when you learn the IPA."
Indeed, that is true.
You also wrote, "Now, maybe it's harder because nobody bothered to name the IPA characters."
Bingo, and the character names are just a mess. I think that most speakers of English get that "shingle", spelled s h i n g l e, where each character has a single syllable name, much more easily than Esh, small capital I, n, lowercase script g, l
I certainly never looked at the word shingle, phonetically transcribed, and ever thought about the characters in the way I do when reading text. Perhaps I'm odd. But I would no sooner condemn someone to work with phonetic transcription who's blind, and expect ease and proficiency, than I'd expect them to fly to the moon using their arms as propulsion. And I'll be the first to admit that there are plenty of sighted who never get the hang of the IPA, either. And heaven forbid you're going to deal with phonetics across languages, some of which take forever [if ever] to retrain the ear to even hear (or the brain to process) when those are not linguistically significant sounds in your first language, then having to put those down on paper in the IPA! Thanks, but no thanks.
But, to each his or her own. Some people like challenges that I'd sooner avoid.
Brian - Windows 10 Home, 64-Bit, Version 1809, Build 17763
A great deal of intelligence can be invested in ignorance when the need for illusion is deep.
~ Saul Bellow, To Jerusalem and Back