As for Merman not acting the dramatic parts well in the 2nd Act of GYPSY, I have to disagree and say that she was dramatically powerful in her confrontation with Herbie over her having Louise take the stripper part and Herbie's decision to leave Rose. She held Herbie's hand on her shoulder when she asked plaintively, "Herbie... why does everybody walk out?" with her voice cracking. And then a few lines later, her sad but defiant "You go to Hell". She was very moving in that scene.
I have a few thoughts on the different ways that the various Roses have handled the theatre audience's loud applause following the completion of the singing of "Rose's Turn". I don't honestly remember how Merman handled it, following her very effective delivery of this "nervous breakdown" song, other than letting the applause engulf her. I do remember Lansbury's way of responding, which differed in the pre-Broadway London production which Laurents directed also. In London, she did not continue bowing after the audience's applause stopped. In NYC, she DID continue bowing after the applause stopped, after delivering a searing, almost too angry rendition of "Rose's Turn". I personally thought that the continued bowing was overkill, with Laurents possibly feeling that the audience wouldn't "get it" unless the continued bowing made it clear that it was all in Rose's head. Tyne Daly, also directed by Laurents, performed it with a less angry "Rose's Turn", but with the continued bowing. I think Bernadette Peters also did the continuous bowing, even though she was directed by Sam Mendes.
Personally, I like the way Patti LuPone is handling the response to the audience's applause better than all of the previous Roses: She milks the applause and basks in its recognition of HER, if only in her imagination. Once the applause finally dies down, she does NOT continue bowing or milking an imaginary applause; she doesn't need to because we, the audience, get it. Her "Rose's Turn" is on a par with Merman's, and her response to it even surpasses Merman's.
The whole applause situation has another factor to be considered and it was Oscar Hammerstein, mentor to Stephen Sondheim, who
enters the scene. During the writing of GYPSY, Hammerstein was asked his opinion about various aspects of the book and score. He noted that all of Rose's songs ended in either a blackout, a scene change, or a first act curtain, with the star of the show not being present on stage to receive such applause. Hammerstein pointed out that there was a need for the audience to see the recipient of the applause be present on stage, and "Rose's Turn" fits that need. After that there is a brief coda of dialogue with its tentative healing of the wounds inflicted by Louise's confrontation with Rose in the dressing room, and then the final curtain can fall. In the present production, Rose has a silent reach towards her name in lights as it slowly dims and goes out. Rose now has to move on. Then the curtain falls.
"Madam Rose...and her daughter...Gypsy!"