(I figured after yet another day o' bugs, it was worth playing the song...)
There are three things I love about watching various version of Idle singing his iconic song. The first is that by this point, they try to find somewhat clever, subtle ways to bring the song in. (And they do that very well here.) The second is that Idle really seems to get a great deal of pleasure singing the song. Mind you, he may not, but it doesn't come off that way. It comes across that he knows he wrote a really, really, popular and fun song that people really love, and he takes great pride and affection in that. (And it's important to remember that unlike a singer who has to perform his Big Hit Song at every single concert, every night and do so for decades, perhaps singing it 5,000 times -- Idle sings it on Occasions. There might be a lot of occasions, but it's probably more like 50, rather than 5,000. And the third thing is...well, it's that it really is a truly fun and catchy song.
This version comes from an appearance on the generally quite-enjoyable The Graham Norton Show.