Peggy Seeger said, "If you find yourself listening to the instrument, the song is not working"

I have to respectfully disagree with Peggy here. There are plenty of songs where the arrangement/instrumentation make them.

Whether it's to your personal taste or not, I think you'd be hard pushed to suggest that, despite its lyrics being completey meaningless, Procul Harum's A Whiter Shade Of Pale doesn't work.