Something crazy happened, when I recently looked up some details in Chopins 2nd sonata! There's no manuscript unfortunately, but instead quite a reliable source in the manuscripts copy by Adolf Gutmann from the year after Chopin having finished the sonata.
We know that there's a repeat of the exposition, jumping back from the first Volta to bar no 5. I.e. here in the Paderewski edition, but as well in every other common edition ever since.
And now take a look at what's written in the copy from 1840.
As we can see, the Volta is written, but there's no repeating sign in the beginning. The repeat seemed kind of suspicious to me for a long time. You can't really combine the harmonies fluently.
But even after discovering that - I'm still not convinced in repeating the introducing bars also. The form of this movement has got much more strength than a usual classical sonata. And especially these first bars are full of the kind of gravity you can rarely in music or words. Imagine I'd repeat 'To be or not to be' in a single scene a second time, no matter for what a reason.. the sentence would lose it depth and content completely. And it's almost the same with the very beginning in Grave.
I'll continue to seek for a convincing solution. But at the moment I tend to not play the repeat at all. The movement tells me a story, rich in colors and pictures, and I feel no need to repeat a single phrase.
Possibly this is only a relic from Chopin who had been told at a younger age that expositions are supposed to be repeated. And that's it!
I'm not the first one thinking about that for sure. But what do you think, do you agree with my theory? Perhaps we're gonna discover something else in the manuscript which could turn inside out our entire understanding of this music. We have to be aware.. :)