The trouble is, a lot of the entries in the DT are transcribed imperfectly by ear from a recording. If you're not familiar with a particular place or personal name, you stick down what it sounds like.

But nobody has ever sung it the way you write it.

I think it's this sort of error Marcus wants to correct, rather than saying the Duke must be Grafton, not Grantham or Bedford or whatever someone else sings.

WassaiL! V