I saw John and Mary twice at St. Bonaventure University in the early 1990's - I want to say 1991 and 1992. When I went to that first show,
1) I had John Lombardo sign my copy of Hope Chest by 10,000 Maniacs - the same copy that Natalie Merchant signed and yes, he signed it first.
2) I purchased their first album, Victory Gardens, and yes, they both signed it.
They were both exceptionally nice. And exceptional performers.
When I went to that second show, they BOTH remembered my name. And were happy to see me.
Now, technically, I saw them a 3rd time at St. Bonaventure, in 1995, after Natalie Merchant left 10,000 Maniacs and that band appeared essentially with John and Mary instead of Natalie - a lineup that pretty much has stuck to this day (John is only a part-time member and Mary did leave the band for awhile), so there's not a lot of John and Mary music anymore, but they don't not exist and they still make music together.
This was their debut single and the song they opened with at that first show.