My advice is to go down two posts and listen to these in reverse order: first the Michael Grimm; then the Terry Reid; then the Lorraine Ellison.
Lorraine is the original, and it's a great story. Don't quote me, but the story goes something like this: the band was in the studio for another session, and there was time to kill while everyone was still getting paid. The producer had Lorraine handy, with a song and charts, and with limited time they cut this in one take. That's pretty close to the truth anyway, close enough for this non-rigorous blog for sure.