for anyone who missed KC's link, this is from Heart's own website ... doesn't read like separate sets .. and seems clear that the set belongs to GPN

<i>" Ann &amp; Nancy Wilson are one of the surprise guests on VH1's Diva's!! They will be performing with Grace Potter and the Nocturnals."</i>  

I don't really care What song(s) they do together - both GPN and Heart can handle different styles with ease - just happy to sit back and enjoy the power surge that Grace and Ann will generate