Midchuck, I'm with Dick on this. But I think you missed a key point. Whether a trio can take three turns without being irritating depends on what they do with their turns, especially whether they "insist on ... group material."

If each member of a trio wants to sing another song with the trio, there is likely to be a certain numbness setting in amongst the listeners by the end of the third song, particularly if all the material is similar or is part of the group's standard repertoire.

If the members perform varied songs, if each singer is not joined by the entire group, and if the musical styles are varied, it's a very different experience.

One case is an unsolicited mini concert. The other is three people taking their turns in a singaround. ... Just my 2 cents....

Rita F