there's a pulsating of the forearm with each chord. But this is how I play it. I'm sure there are many other valid ways of getting through it.
I think the difficulty is that if you don't do this you have to kind of stretch/pull your fingers over each other. Particularly problematic in this situation since you have to lift and pull fingers 3,4,5 against each other..
When the forearm supports the motion, the fingers are lifted and then placed down onto the notes, they never stretch and twist around themselves and always remain comfortable.
Is that you're thoughts birba? When I first learnt the polonaise this was one of my problems and I could never play this section with any real excitement the way the music demands.. the forearm motion was what made the different for me..
I will have to try your fingering also birba.. seems like an interesting and valuable idea to explore.