MikeofNorthumbria wrote on 8 January:

Now there are many British singers who love American folk (and jazz, and rock) music ... [a]nd the songs they love to sing have speech-rhythms that are just as distinctive as Shakespeare's. To sing them convincingly, it's essential to understand and respect those rhythms. ... [T]he Beatles sang Carl Perkins songs for exactly the same reason that Orson Welles played Shakespearean roles – because they found them irresistible.

I think that's exactly right. And the same goes for Yanks who sing Scottish songs with Scots pronunciations.