I remember there was a song by Grungetta and Oscar singing about their favorite transportation called "The X-Train". It starts with Gordon thinking why are they arguing. And Grungetta and Oscar told Gordon they are not arguing they are going to sing a song about "The X-Train". I love the refrain part with the two train conductor grouch muppets goes "Grumble, Grumble, Grumble, Grumble, X-Train! Grumble, Grumble, Grumble, Grumble, X-Train!" Sounds like Marty P. Robinson and Richard Hunt are doing the train conductor grouches.