That's when it hits me -- it's one of those syllabic spoonerisms, a variant of "West of the Rockies," no doubt trying to isolate the word "rock."
Now, I was 18 years old and living in London when that album came out in 1975, and I was already losing interest in Reg, thinking he'd been on a downturn since "Caribou." (I do give serious props, though, to 1983's "Too Low for Zero," with its iconic "I'm Still Standing." I used to time my sit-ups to that track, in the days when my abs still showed.) So I wasn't too familiar with a key American geographical distinction, which functions a bit like England's "North of Watford*."
But there it is. It's taken me 35 years to get that joke, and I hereby claim the world record for being dull.
Not to be coy about my classical education, a phrase from Homer springs to mind: "Doh!"
*Supposedly where the green, sophisticated south ends and the dark, satanic mills of the smoky industrial north begins, even though it's only about 20 miles out of London. Elton John is part-owner and life-long president of Watford's professional soccer team. See how it all comes together?