The English do it well because all they have to do is slow down their speech to do Southern, and speed it up to do Texan.You've certainly got my sympathy. I'm on a lifelong crusade against the Hollywood "southern" accent, which sounds like no southerner I've ever met. I can immediately pick out who actually has a real southern accent (like e.g. Holly Hunter) or who actually bothered to study (e.g. Kyra Sedgewick). Ironically, British actors seem to be really good at American southern accents. Probably because they don't bother trying to mimic other actors.