I agree with your close reading mostly.
As to Paulˇ¦s ˇ§elastic power of claiming the moment, mounting with it, and finding it all sufficientˇ¨ my opinion is
that it shows how deep Paul sinks in the music and cares nothing but his own happiness. He doesnˇ¦t think more
and just want to enjoy this kind of feeling.
Yes, that's true. But I also think that it takes a lot of imagination (elastic power) to just live in one moment and forget about the others.