At an open stage on Monday, I heard a musician play some adventurous and nicely designed music he created on his iPad. He utilized portamento and glissando features which distinguished it musically and made it more memorable, to me anyway. Then one piece started off with more syncopation and an excited young woman seemed compelled to loudly clap her hands, slap her arms and stomp along with her feet. It is a tricky situation because an audience participating is in theory a bridge between the performer and the crowd, maybe it is unifying but the downside is it locks the rhythm and repositions the performer to now be at the mercy of how good (or bad) the audience is at clapping.