The best example of the American southern dialect written phonetically is Mark Twain. I hated trying to read Huck Finn when I was 6 but now it seems full of flavor and music.
But then again I was used to hearing the dialect so could understand it when it was written.

Robertsons posts drip with the sounds and music of the language of his area. Unfortunately I have very little experience hearing the language so have no point of reference for my brain to make the connection of the printed word to a spoken sound.
The regional idioms I am totally in the dark about.

Here in Canada it is an amazing melting pot of cultures and languages and I'm just as clueless sometimes. Particularly when it is a young person talking.
Here's one I heard at the Museum last week. See if anyone can decypher this.

"Like Moi, y'all eh?"

When coming from an 11 year old I doubt it was an affectation.

It meant "Wow, I get to go with your group? cool."