That is a line worth remembering! As a confirmed Northeasterner, raised in the shadow of NYC, I generally run screaming from the South. However, I have spent some time there and thought about related issues. It seems to me that Southerners are more concerned about "how things look" to other people, and tend to put more of a premium on "playing nicely" at least for public consumption (Think of Texas' driving motto "Drive friendly!"--yeah, right.) Thus I so think the sweetness is a social veneer--not necessarily covering that memorable "odeous bile"--but a fairly thin layer nonetheless.
I don't think they are inherently any nicer or less nice than anybody else, but it's apportioned differently--more stratified, I might say, enriched at the surface rather than spread more evenly throughout.
Of course, these are all generalities. Perhaps I should shut up so we can hear from more people who actually live there (poor things....
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