A full video with Mandy Patinkin has appeared on YouTube (must be very late in the run when Mandy came back for the last few weeks) and it's just fascinating to watch. I realise Betsy Joslyn was technically the first replacement, but given that only seemed to be for a couple weeks to fill in until Maryann took on the show for a decent amount of time (6+ months) It feels like Maryann was the first 'real' replacement. And this is the Dot that would have been playing when the show won the Pulitzer.
There is also a video on YouTube of Betsy and Robert Westenberg (aka the Solider or the Wolf in Into the Woods) singing 'Move On', followed by a SPECTACULAR performance of Bernadette and Mandy singing Move on (Bernadette in spectacular vocal health, much stronger than what was actually filmed).
I guess a couple observations that:
* It seems that all the Dots I have seen in this production do fit a certain mould to fit the tone of the production - a bit odd looking and sounding with unique strong Vibratos. I can easily see why they went with Plunkett instead of Patti LuPone - Plunkett is very much tapping into the original Bernadette energy and sound. I think this is the kind of sound I did miss from Ashford in the most recent revival.
* There is something a bit haunting about the vibrato of Plunkett - almost a bit Betty Buckley sounding. Someone on YouTube complains that she sounds off-pitch the entire time. I can hear what they are referring to - I'm not sure exactly if it's pitch or the timbre of her vibrato or both but I do find it a little haunting.
* Based on all these clips, would have been amazing to see and hear them all. Of course, no one can really quite do what Bernadette did.
Did anyone see Marayann Plunkett live? 
I can't find much written about this in terms of reviews, bur Maryann Plunkett did comment on what it was like to be a replacement in 1986 and 1987:
https://www.nytimes.com/1986/09/17/theater/me-and-my-girl-co-star-in-her-own-role-at-last.html
"She replaced Bernadette Peters as the star of 'Sunday in the Park With George.'
I had replaced so many people, and I think you get into a replacement mentality,'' she explains. ''It's 'get going, get into the show, don't ask questions, just do it.' When the cast has been doing the show for a year, you have to look like you're not a sore thumb.
"
https://www.nytimes.com/1987/06/14/theater/when-it-s-a-hard-act-to-follow.html
"
Maryann Plunkett felt that ''Sunday in the Park With George'' was ''the type of show that doesn't come around every day. So when I got the opportunity to do it, it was a dream for me. But replacing Bernadette was very difficult, because she was so loved. It wasn't a case of someone who was just good, but she was loved both on stage and off stage - not only by the audience but by the company.
'Being a replacement is like being a stepchild coming into a family that has its rhythms, its life, its love, and then suddenly you're faced with the problem of wanting to make the part your own at the same time that you're wanting to fit in and to make friends. So then you're confronted with the realization that it takes time, and it's hard getting through that period until you do fit in. In 'Sunday' it all happened in two weeks.'"
I think Victoria Clark was the understudy and mentioned the standby being awful to her — would that be Maryann? This is very off-topic, but it always amazed me how poorly they kept casting George after Mandy departed. Like, good voices, but the acting... https://www.tumblr.com/through-my-memoirs/142134040703/cris-groenendaal-sings-finishing-the-hat-from?source=share
I believe Plunkett was never an understudy or standby and therefore it’s unlikely Victoria Clark would be referring to Plunkett.
binau said: "I believe Plunkett was never an understudy or standby and therefore it’s unlikely Victoria Clark would be referring to Plunkett."
Joanna Glushak was Bernadette’s understudy and filled in for her when she went on vacation.
Broadway Star Joined: 7/18/11
Yes, I saw Maryann. I also saw Mandy, and it was so close to the beginning of his return that my Playbill had a full page insert with Mandy’s photo and bio announcing his return, as they hadn’t printed new Playbills yet. To be honest, I don’t remember much about Maryann’s performance. I remember a lot about the show, but not anything specific about her performance. I was a couple months shy of turning 10 years old, so that may have had something to do with it.
Broadway Legend Joined: 4/22/04
I saw the original ''Sunday in the Park With George'' a number of times (often doing standing room). So I caught Maryann Plunkett, too, but like pmensky, I can't recall the specifics of her portrayal per se. I also saw her Tony-winning performance as Sally in ''Me and My Girl.''
And Plunkett will be returning to Broadway this spring as the older Allie in ''The Notebook'' musical.
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