You see this sort of thing in Debussy too. To our modern "scientific" minds it doesn't make sense to combine pedal and staccato: of course it's going to sound legato. But the point is that if you think of it as staccato, then you'll instinctively change other aspects of the tone quality too.
In this case, in my opinion, the point is that the right hand is clearly split into melody and accompaniment, and you want the accompaniment to be a lot softer than the melody. It's different from the other Chopin double-note etudes, opus 25/6 and opus 25/8, where although the top notes should still be louder, the two voices can be more equal because they're basically doing the same as each other. In this one, the staccato markings should encourage you to use a much lighter touch on the lower notes, making the difference between the two voices clearer.
Thank you, Alexander. That's very helpful! I've been practicing this etude without any pedal, which is not easy for me because my LH wants to copy my RH and play staccato too. So I was working on holding down the LH for a complete beat, but getting off on the rest, and then of course making my RH play the upper notes legato and the lowers ones staccato. I still have to work on the pedaling though.
Regarding pedaling with staccato - I'm also working another Chopin cutie - the no. 18 Prelude
. I'm totally at a loss as to why there are pedal markings toward the end of the piece. I’m attaching a part of the document – it’s the middle line, last bar. I don’t understand why Chopin marked pedal down on the first notes of each pair of eighth notes. These are also marked with a staccato, which you totally lose when you use pedal. I think you’d get a much sharper and grittier sound without pedal, and then really attacking the accented eighth notes. I dunno…I just have so many questions lately….
@Stu – Yes, it sure would be nice to be able to put up more than four pages without having first to rig up some kind of board or something. The only problem I see with having an extended music rack is that I might not be able to see the far end pages. My dumb eye sight seems to be getting worse and worse and I would have to keep a pair of binoculars on the piano. But I really like your idea of a horizontal escalator! That would be very cool!!