I'll tell a funny story about a Q&A I saw with the Avett Brothers. They were asked about the meaning of a particular song. After they answered the question, Scott just started singing it, leaving Seth to catch up on guitar. Seth looked surprised, started playing and laughing. After the first verse, Scott realized they hadn't played it in a while and looked at Seth saying "I can't remember the words!" Seth just laughed and said "I know!"
At that point, Seth is just vamping on the guitar while the audience is singing the song to get them back on track. Except for some reason, the audience was singing the THIRD verse, not the second. Now the story was out of order but what the heck, everyone had a laugh.
Obviously, I'm telling this story as a good, funny memory. Had they handled it differently, my perception may have been different.