We've seen him play in a few small venues over the years. That board that he taps his feet on is a big part of his sound.
One show we saw consisted of a three-person song circle with Chris, Jorma K., & Patty Larkin. At one point, the three of them began a song together, but Chris soon stopped playing his guitar and just sang harmony while Patty & Jorma soldiered on.
After the song ended, Jorma turned to him and asked "What, can't you play in G?" LOL
I think Chris was simply enjoying what he was hearing the other two play, and chose to sit that tune out. Funny, nonetheless.