This is such a fascinatingly original cadenza! I leave aside the technical bravura (which is, however, extraordinary), I'd like to concentrate on the music: Hamelin achieved to give new breathe to this work which (alas!) has suffered so many mediocre performances.
His writting is brilliant, his ideas clear and well defined, his melodic choices are utterly original and daring. See how the main themes of the Rhapsody here interlock in such an ingenious way! All in all, a masterpiece, this cadenza! I discovered, today, the score (on youtube) and I was able to admire, once more, the excellent work of this great pianist - undeniably one of the greatest in the world today.Here is the score: