I won’t take offense at your comment that a Tennessee accent is relatively simple, but I still submit that Southern accents are not that easy to pull off consistently. I have lived in Ga all my life and I can easily tell the difference between true accents from the Georgia towns Savannah, Macon, Atlanta (old monied) and say, Dahlonega. They are all different and none like that affected dialog from Gone in the Wind, at least from the white actors.
But even a Georgia hick like me could tell that DVDs accent was, well, ‘orrible. I got stuck in a pediatric waiting room room with it on recently and I was looking for the gas pipe . . .
I even give the accents names. “Dolly Parton Twang” “Rosamund Carter midland Georgia” “Rhett Butler Tahd-wahtta (tidewater)”