Kevin Clash was telling a story about how Jim Henson was supposed to do the lead part for this song, but at the last minute he said “Kevin, you should do this part - I think you’d be better at it”. So Kevin is now the main character, and Jim takes over as the blue Muppet in the ensemble. Important sidenote: Jim was the one who taught the ensemble their choreography for this song. Basically, Jim decided to give someone else the main role so he could upstage everyone else and goof around. I just watched this for the first time today, and it’s hilarious!