The 70s song that had... EVERYTHING

I am reading THE ATLANTIC (and a great story on the modern Hollywood paparazzi) and listening to some 1970s music while waiting for BRISTOL ROVERS to host WEST BROM in the FA Cup quarterfinals.
My 70s playlist just served up "HOCUS POCUS," the 1971 progressive rock opus by Dutch band FOCUS that somehow managed to crack the U.S. Top 10.
I really shouldn't be surprised the song shipped so many copies -- it is jam-packed with every possible element you could imagine!
MEMORABLE RIFF? Yeah.
FLUTE SOLO? Check.
YODELING? It's in there.
WHISTLING? Uh... oh yes.
POUNDING DRUMS? In place, thank you sir.
The song has everything, that is, except comprehensible. There's some rather high-pitched gibberish at the three-minute mark, then that crunching guitar comes back into play.
Inspired lunacy. They just don't make them like "HOCUS POCUS" by FOCUS anymore. Whoah! There's that flute again. When do they yodel again?