Many thanks to friend of OPC Gavin for posting the following on a long-dormant thread:
I can't believe I didn't think of this one at the time: in Nirvana's "Sliver," Kurt Cobain sings "Grandma take me home" 43 times (by my count). This knocks BTO off the leader board, and is even more impressive when you consider it all happens in just 2:17.
It seems to me that Nirvana did this sort of thing - heavy repetition of phrases that were not the title of the song - quite a bit. Kurt sings "Ann Maria" an awful lot in "All Apologies," for example. It's kind of a way to adhere to pop convention and disregard pop convention at the same time; Abba, I think it's safe to say, would never have given "Take a Chance on Me" a title like "Lithium."