http://www.youtube.com/watch?v=X7mdy...elated&search=
well, not always
... the first minute here is a bit embarassing (then it gets better)....but they were a bit scared , probably, "network television debut". "LETTERMAN, whooo, guys we're playing letterman tonight I'm scared!" I can totally sympathize - for real.
BTW, you're right, I've seen many really nice live performances.