What he said.
Except, I'd say that it comes from a LATE 1977 version, instead of an EARLY 1977 version...in those early 77 shows, Stevie was STILL belting it out with the same fervor as in 75/76, it wasn't until MID-77 that the dynamics of her vocals within the song changed. Compare versions from the March 77 San Diego show vs the August 77 Las Vegas or Los Angeles shows.
Plus, it's a dead giveaway that the
Live 80 album is not what it is advertised, since (even BESIDES the early arrangement of "Rhiannon") they never played "Don't Let Me Down Again" on the
Tusk tour...and hadn't played it since early 1976 at the latest.