We do that in the jazz combo that I'm occasionally part of. Out of the 5 of us, there are two bassists, three horns, three keys, two drums and two guitars. It's a lot of fun, particularly when myself and the other horn swap over on keys in the middle of a song to accompany each others solos!
Yes, yes. Some people, which are visiting our gigs already know it will come, but nobody knows which combination we will choose...