I recently performed at B.B. King Blues Club on 42nd Street in New York City. The band was well-rehearsed; the staff fed us well and poured red wine (and Red Bull) down our gullets, treating us like the swell blokes we are. Our friends were there, plus lots of strangers. The sound crew did a great job. We even had chord charts right there in front of us. Yet we all made careless mistakes here and there.