A lot of us have no pretense to professionalism, have no CD's we are trying to sell, and still like to sing. And we appreciate people who have made efforts to learn songs. Bringing a copy of RUS to a session shows absolutely no effort in learning a song. And we are indeed getting together in groups, parties etc.--where even cheat sheets, possibly little books of lyrics of songs you like to sing--which you therefore have shown some effort in compiling, etc. are fine--but RUS is not.