I once substituted a Bb9 chord in place of a straight F chord in a trad tune, and was promptly reprimanded by the listener.

For a long time I refused to mute the bass strings on my guitar (for that Doc sound) feeling that for what I spent on my rosewood guitar, the guitar should be allowed to sustain and ring out. I was told by a famous and notable player that my attitude was the most assinine thing he'd ever heard of. I decided that HIS attitude was more assinine than mine (but I did learn the technique.)