Meaning of "used to would" double modal?

[Jesse Sheidlower]

A friend encountered some examples of the "used to would"
double modal in a song by a southern performer. I explained
the general idea, but he pointed out that in the examples in
the song--things like "lies I used to would tell" or "people I
used to would hate"--the "would" seemed redundant, and he
asked if the double modal was emphatic, or random, or what.

I don't actually know, and figured I'd ask here rather than
trying to make something up based on the few resources for
this that I have handy.

Thanks for any input.

Jesse Sheidlower
OED

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