I've always appreciate that most other languages seem to have a plural you (e.g, tu vs. vous), and just figure that Southerners have improved English to include one. My wife believes that Southerners use y'all as a singular (like talking to just one person, they'd still say y'all for you), but I told her only really ignorant ones do. All y'all is simply a more inclusive plural you, like in this example:
"All y'all can come on over." followed or preceded by a gesture to a large group. Looking at just a small group within a large one and saying, "And y'all're welcome to invite some more folks to come, too. We got plenty o' fixin's." would distinguish between the smaller y'all and the larger y'all.
See how much clearer that sentence is without the ambiguous "you" to refer so non-specifically to one person, several, or a lot? And for the record, y'all isn't even improper English - it is a contraction of "you" and "all". It's not like "ain't" for "isn't" or "aren't". It is the way someone should contract those words. Ah, the beauty of the English language. So bizarre, and so flexible.
Y'all come back now, ya here! Tomorrow's post is about semantics.