I bought this album when it was released with paper route money. It's still one of my favorite of all time.

Thanks! 👍

First, Nancy plays the intro from Crazy On You, and it's live, because it's different than the record. (I learned the record version long ago, and she does a few things differently. )
Then the song itself is lipsynched. But, they went through the trouble of having Roger Fisher play a banjo, which wasn't miked or plugged in.
I enjoyed it and I've always liked the song. But, the video caused me some dissonance.

Even if the song is lip-synched (the intro probably isn't, as ProfGAC mentions), it's still great to hear. Audio engineers consider Dreamboat Annie to be one of the best rock recordings ever. There are performances on that record that are right up there with John Lennon's "Twist and Shout" vocal. It's amazing to be able to capture that in a studio environment. And the overall sound of that record is just so big--you can really hear why so many recording artists and engineers still prefer old analog and vacuum-tube technology.