Talking of "Off Key" singing. Alongside the redoubtable FF Jenkins, you could line up Mrs Miller (Who's eponymous 2nd LP "Will success spoil Mrs Miller?" rarely leaves my turntable.)
Travelling into Europe, who could ever forget MA Numminem, whose rock opera on the subject of the philosopher Wittgenstein, "The Tractatus Suite" is a joy and a wonder.

We could always add at this juncture, those 2 celebrated doyens of Mudcat threads over the years, William Shatner and Leonard Nimoy.
And Jo Staffords benighted alter ego. Darlene Edwards!
Linda McCartney anyone?

Seriously. I think the original post was basically correct. The likes of Dylan, Waits etc. all have something to say. A case of the message not the messenger. But it's a fun thread nonetheless.

And the thought of Ian Dury as a computer software expert in Milton Keynes cracks me up!!

Nowadays I just wish I was the MD of Antares corp. (For those who don't know..It's a digital pitch shifter!) He must be making a fortune!!