Gaughan said "can only use it to construct a useful *theory* of rivers" not "can and should "construct a comprehensive and accurate description of rivers."" Point is, performers don't describe rivers, they jump in and float with the current. Performers sing songs that are meaningful to them. If the songs mean something to other people, then those people will sing them. It isn't any one person's responsibility to keep all the songs (or sides) of a tradition alive. Your argument on "equal time" and your theory about songs being censored by the mere fact that one individual doesn't choose to sing them don't hold water, so to speak.