Seems like a bizarre idea to me. If bands have properly prepared charts, there is no reason why anyone should be unable to do any tune/gig at a moments notice. If you haven't, you are reliant upon a concensus view as to what the song should sound like, which version you are familiar with and whether or not the singer can do stuff in that key. In my experience, the result is chaos. If you have no charts, rehearse. If you can't rehearse, have charts.
Some of the best music I have ever played is music I have never heard before I played it.
(PS Although I have played a few of them in my time, I know none of Jonesies list of tunes (which looks very Rock-centric to me). A Soul band will have a different go to list, as would a Funk band, a Punk band and Pop band etc etc).