Yeah, by the 80's Zappa was definitely "phoning it in." If anyone wants to hear some of his best stuff, check out "You Can't Do That On Stage Anymore Vol 2" ... it's my favorite band of his, with Chester Thomson and George Duke.
He was phoning it in partially because it's a foreign show. He'd said a bunch of times that where english comprehension isn't that great, he sticks a lot closer to the songs.
Song == happy