Malcolm, you may be with Jeri, Don, and Mary on this one, but I'm with Blind Lemon Jefferson, Leadbelly, Woody Guthrie, and a host of others from the American folk tradition who kept recreating songs throughout their musical lives. Look at what Leadbelly did with The Maid Freed from the Gallows, or what Woody did with The Gypsy Davy, or with Lonesome Valley, for that matter. In each case the text and the tune are recognizable, but the song as a whole is as much a creation of Mr. Ledbetter or Mr. Guthrie, respectively. Now jump forward to the early 1960s and see what Bob Dylan did with In My Time of Dying, with Man of Constant Sorrow, and with Gospel Plow. Really something fantastic, as far as I'm concerned. Preservation has its place, but it's primarily someone else's concern, not my own. As I wrote earlier, I learn a song by learning the story, the major aspects of the text, and a recognizable approximation of the melody. Then I combine those elements to recreate the song anew each time. That's my way, no better and no worse that your way, just different.