Thanks so much for listening to the sonata (twice!). I really appreciate it, especially your very kind observations on my playing. Although this unusual, one-movement sonata is still in sonata-allegro form, by its nature and intent, it's very episodic, almost segmented, as you noticed. The challenge, I think, is to tie it all together, meaning concentrating on the long lines, the musical intent and execution, and bringing a direction and sweep to the experience so as to put it across to the listener. And there's a lot to put across there!
On the arm weight aspect, I must give all credit to Nancy Oliva, my first piano teacher of 10 years. One of her professors at the New England Conservatory of Music was Albion Metcalf, a student of Tobias Matthay (1858-1945), a guru of the principles of arm weight at the piano. From a young age I received training in that aspect of execution. And I've never forgotten it and always try to employ arm weight appropriately, as when expressing rich chords. In our day there have been assertions that the sole determinant of tone and volume is the acceleration of the hammer--period--and that the same result can be achieve playing a key with a pencil or the tip of an umbrella rather than arm weight. The scientists with their measuring devices have proven that point, but only when speaking of a single key and the sound produced by it. Despite the intrinsically percussive nature of the piano, the instrument's magic is hardly ever limited to a single note. Instead, musicality has everything to do with creating the illusion
of legato phrasing by connecting sequential tones and shaping the richness of the overtones in the chords with arm weight and the pedal. That far exceeds poking a key with a pencil or umbrella. It's all about creating a sense of lyricism and nuance and, at times, power. So I brush those arguments aside and continue to believe in arm weight.
Again, I'm so glad you enjoyed hearing this marvelous piece.