Chopin C-major Prelude

I like this piece, but I'm having a hard time with some of the rhythms.

The majority of the piece is made up of sixteenth-note triplets in 2/8 time, giving it a 6/8 feel. This is all well and good. But at measure 18 it starts to get complicated. The left hand has a sixteenth-note triplet as usual. But now, the right hand has a quintuplet figure which is damn hard to play as a quintuplet, especially on top of the left hand's triplet.

I can see what Chopin might have been getting at here; measures 18-20 all contain these quintuplet-over-triplet rhythms, and the sixteenth rest is dropped from the beginning of each of these measures (in the right hand), which overall gives these three measures a sort of "anxious" quality as they build up to the fortissimo climax at measure 21. It's as if, in breaking from the normal rhythm here, the piece has seen the goal at measure 21 and is "rushing" there.

I have listened to recordings of this piece (Daniel Barenboim is the one that currently comes to mind), and he plays it wonderfully. However, I can't really tell, no matter how hard I listen, how he's really playing these rhythms here. It definitely sounds different from the normal rhythms, but I can't really say how, other than it does indeed sound "anxious" as I describe.

So, I don't really know how to treat these measures, and I don't quite understand why this rhythm comes back again sporadically as the piece closes. After ms. 18-20, this rhythm comes back again at ms. 23, then again at ms. 25-26. Now, if I try to treat ms. 18-20 "anxiously," how am I to treat ms. 23 and 25-26? In these measures, the piece is relaxing as it moves towards the close.

How do you guys perform this piece?