Actually I had never heard Mustang Sally played at the blues jams I've been going to and mostly know about it from this forum as a song lots of people get tired of playing. Well I didn't know it was a 24 bar blues song (or even that there were 24 bar blues songs) so that was the problem, as you can imagine. the singer kept staring at me and singled me through the changes, but once he started soloing I stupidly ( or automatically) went back to a 12 bar. I started getting so flustered I forgot to look for all the hot chicks that supposedly start dancing when ever Mustang Sally is played!! live and learn i guess haha!!