So I'll start by saying that in terms of everywhere northeast of Mississippi, I think I'm pretty good at interpreting what people are trying to convey. This is helped by the fact that most of the Midwesterners I know are pretty blunt, straightforward people. (It took me a long time to get used to how in Cold State, nobody goes through the "How are you?" exchange when they call - they just ask whatever it was, say goodbye, and hang up.) I will reserve commentary on the Northeast.
But the South! Now that I've had a few months to get over the re-acclimation/ culture shock/ bizarre lime green ankle pants, I think I pretty much know what people are saying. I'm not a sociologist; I don't know why Southerners tend to say "the rabbi's singing is very... heartfelt" when they mean "he's completely tone-deaf and it causes me physical pain to listen to him", but there you have it. Dr. S comes home every week, though, and says "I just don't know what people are trying to say." And I can completely sympathize.
The fact that I grew up here also allows me to smile sweetly and not care what people are trying to convey between the lines. I, too, can speak Southern: I can say "How kind of you to try to help" and let them know that I understand, but don't give a damn.