I'm right there with you guys. I used to sing with a group of friends, one of whom is an old-time Texas black gospel singer,Leo. He knows nothing of musical language (keys & that sort of folderol), but what a singer!
The purpose of our group was to (try to)sing in the black gospel style, but our main piano player (classically-trained piano teacher) just could not get it.
She tried to assign us all fixed "parts", to which we would "stick" & sing the same way each time (so that she could learn one accompaniment, & play it the same each time).
She HAD to write everything down - of course then she expected Leo to sing the same way next time, which he never did.
It was sorta funny, how he was always trying to get her to throw away her papers, but she just couldn't.
Her style clashed horribly with Leo's, & her rhythm didn't even approximate his - & she couldn't hear it.

The term Leo always used for singing that sounds too straight was "choir". If we heard that word, we knew we were in trouble.

What an eye-opener for me. I know that all classically-trained musicians don't become crippled in this way, but her ear seemed to have gotten lost somewhere.

Jerry, thanks for your explanation of how black church singing works. I can show it to my cousin, who didn't believe me, that the accompanists had to work under those conditions (he said to me - "that's just not how music works!") - Me, I think it's absolutely inspiring, & it's my own goal to be able to play that way. Like you, i have no interest in singing in a choir, the same way every time. It's so exhilarating to feel the spirit & listen/respond to the subltle cues of those around you at the same time. Praise God.