Hello,

thinking it over, I have to add some more remarks:

Not every double negation is a litotes: "Not unusual" must not necessaryly mean "very usual". There is an usual way and there are unusual ways to do a thing (the third way is the Army way, ha ha). "Not unusual" can also denote a way which deviates from the usual, but is still exercised by a minority.

Best example I can find: In former times the men of Rügen (German island) used to wear kilts. Even now it's not unusual to find old men clinging to this custom.

But the original question was about litotes in song. I think that you'll find no litotes in folk songs. Litotes is a highly artistic figure of educated speech used by orators (e.g. Demosthenes, Cicero, few modern politicians), but not by the common man in everyday speech. So I am convinced that my former statement about the double negation is valid: double negation in folksongs will be a strengthening of the simple negation.

Wilfried