A friend of mine is in a cover band, we'll call it Band A. They will be playing at a club in a few weeks. Another cover band, Band B, is also on the bill that night. One of the members of Band A came up with the idea of both groups being on stage at the same time and taking turns playing one song at a time. He has these ideas that the non-playing group would cheer on the playing group, collaboration between the two bands on some songs, the ending of one song transitioning seamlessly into the start of the next one, they could throw in duelling drum solos at some point, etc.
I've never seen or even heard of such an arrangement. Have any of you ever witnessed such a spectacle? Did it work? Or was it a train wreck?