"If it ain't broke don't fix it!"

Or, allowing for the linguistic pedantry/rigidity of the Tunesmiths of this website:-

"If it is not broken do not attempt to repair it."

I'm rereading Pete Seeger's "The Incompleat Folksinger" at the moment and he touches on the rights and wrongs of 'improving' or rewriting all or part of a song quite a bit. In this connection he mentions that somebody decided to 'improve' Ed McCurdy's "Last night I had the strangest dream". When Ed McCurdy found out about this, according to Seeger, he hit the roof...........