I'm wondering too.It's one of Schumann's best compositions. Perhaps it's too modern for the average audience? That's what Clara thought.
Perhaps too modern when Clara was alive.
I've been looking at this sonata. It is fantastic, a personality like the symphonies. I recently saw Yakov Kasman play it, coupled with another neglected work, the 1st Sonata of Rachmaninov (which I greatly prefer to the more famous 2nd). The Schumann deserves more performances!
...I think it is underplayed because it's very difficult to learn? A friend of mine learned this sonata recently, and for her it's tricky to memorise...and this is coming from someone who had performed Carl Vine's second piano sonata from memory...
"..According to what I read, the first movt doesn't quite make a satisfying sonata form movt and the last movt has problems 'because of its wealth of material'"...I've played it, and I'd like to give some of my opinions on it. I don't think the last movement has a wealth of material, it's rather a long succession of ideas wich is then repeated in a different key. And then it all ends with a coda. In between he takes you through a multitude of modulations, where for example the main theme (the chordal opening) goes through, I don't remember, 5, 6 or 7 different keys all together.Sonata form, well, he follows standard (Beethoven etc) formal procedures almost to the letter. Strangest is perhaps the development, which he almost repeats note-by-note, but in a different key; sort of a "double development" section.
btw, I've got Pollini's rec coupled with the fantasie which I thought was awful
Still nowadays *methinks*