I don't understand how anyone could feel comfortable singing a song they knew was written by a child molester. Doesn't matter how much I liked the song, it would just feel horrible.

I had precisely this kind of experience recently. I was checking out recordings of Etudes by Frederic Chopin. I came across recordings of them by Wilhelm Backhaus. They are amazing - really beautiful performances that are genuinely innovative, witty, and manage to sound very modern and complex.

Wanting to find out more about Wilhelm Backhaus a day or two later, I discovered he was complicit with the Nazis in wartime germany and gave a private recital for Hitler.

It just immediately put me off wanting to listen to them ever again. And if I ever did, all I would hear would be some music by the guy that played for Hitler.