Yep, I agree with that sentiment, at least in part. I think that the participants have an obligation to listen to the version the singer is doing. The singer has the right to interpret a song as they "hear" it. For me, this means I may enunciate, or add dynamics as I want to interpret. Drives me nuts when someone insists on singing along the way they know the song, instead of listening and then going with me. When it is their turn, please, by all means, sing it like you want. But please give me the courtesy of interpreting it as I hear it. You don't have to like my version, but don't try to change it on me while I am performing it. I just saw this done to a singer recently. She was doing her interpretation of a song, and doing it her way. Another fairly well known singer insisted on chiming in and doing it her way. I wanted to scream at her to sit down and let the singer sing.