Who is right in this case?
I believe that this question is fairly meaningless, in spite of my strong feelings on the subject. Interpretation will always be just that, and in such a case where the composer is 150 years dead and reputable sources have contradicting opinions, it is up to each performer to decide what is right for them.
I know that Mikuli is a trustworthy source, but this Paderewski book claims, and this is word for word in the book, “ it is based primarily on Chopin’s autograph manuscripts, copies approved by him and first additions."
Here is a direct quote from the Mikuli edition:
Lamenting the innumerable errors found in earlier French, German and English publications, [Mikuli] sought to provide the reader with a reliable edition based on several sources - especially printed scores corrected in Chopin's own hand; scores in which Mikuli himself noted down the composer's comments during students' lessons; and significant reminiscences by discerning witnesses to Chopin's rare performances.
I also have a Scholtz edition that agrees with Mikuli on the diminuendo, though I trust it mainly because of Mikuli.
And here is what it says regarding the measure with the diminuendo/crescendo. “Bar 45 – The French Edition and the German Edition give a long diminuendo sign after f, and the word diminuendo. The Oxford edition, however, adds scrscendo after f in bar 45 and fff in bar 46. In the copy belonging to Madame Jedrzejewics, this crescendo and fff are also written in pencil in place of the word diminuendo, which is crossed out.”
I would question, certainly, why the original marking was discarded, and by who.
I can appreciate both versions as I play this piece, first one way and then the other.
It's good that you can at least appreciate both. I know I do - when I first started working on the piece, I didn't even notice the diminuendo marking, and simply played it how I wanted to play it. My mom had marked out the diminuendo, as well. It took a lot of consideration for me to appreciate the original marking.
However, the crescendo does seem to make better sense to me as it leads to the reinstatement of the main theme in a final and triumphant manner.
Can the final statement of the theme truly be considered to be "triumphant", though? It seems rather...reserved, to me. Questioning, even. Especially considering that C-flat in measure 47, which creates a completely new variation of the theme.
I did misspeak earlier, though, about the calando section, which I believed started in measure 60, which is where I perceive the climax to resolve. The calando isn't actually marked until measure 68, of course.
And I believe the lead-in to the climax actually begins at measure 42.
The tension starts truly building in measure 36, and it's a beautiful passage, certainly. It just doesn't speak to me as a climax, because it leaves so much unresolved, and I feel that measures 56-60 resolved all the remaining "questions" of the piece, with 60-the end being sort of a reminiscence of the whole ordeal - I know it's odd to put music into words like that, but I guess I can't think of any other way to describe it.
As to your question, I don't think Chopin followed any form with the nocturnes.
All of them do have form, and many of them are similar in form, but it is true that they don't all follow a particular form.
And if he did, the section that you believe to be the true climax is actually a secondary climax. However, I think it is all part of the end.
And we're back to interpretation again, which is fine, of course.
All in all, I am not an expert here, nor am I very analytical when it comes to music. I just want to play it the best I can. I do appreciate all the information I can get about Chopin's music, though, so if you have any other insights, please don't hesitate to share them.
I love analysis, personally - it's just a passion of mine. I discovered a love for music theory in college, which of course just deepened my love for Chopin exponentially, as I feel he accomplished, harmonically, what none had accomplished since Bach, and he essentially brought Bach's principles into the 19th century. I used to analyze Chopin in my free time in college, but I don't claim to be an expert, either. Not by a long shot.