Muzio Clementi - The Genesis of the Modern Keyboard, and the Romantic...

Why is it that the piano music of Muzio Clementi is heard less than it should be?
The world of music recognizes this composer; however, as Horowitz once wryly said, "I am famous, but not well-known." Another way of reasoning with this dilemma is the simple fact that both giants we call Mozart and Beethoven were two of Clementi's contemporaries; therefore, partial historical obfuscation, and justifiably so, seemingly.
Clementi was born four years before Mozart, and eighteen years before Beethoven. His keyboard abilities thrust him into the world of music as a precocious performer before he was out of his teens; more importantly, however, his forays into composition became his primary pursuit before very long.
To put this man into proper perspective is best projected in our time by an occurrence in Milan in an old book store. The wife of Vladimir Horowitz, Wanda Toscanini Horowitz, happened to be in this establishment and came across the keyboard music of Clementi, which she purchased and presented to her famous husband. The result was an instant infatuation with a palpable amount of the material in this collection, and an assiduous championing of Clementi's music in countless performances of the Italian genius in recitals which Horowitz gave, virtually up to the end of his life in 1989.
What obviously gripped Horowitz (remember that Horowitz was already middle-aged and firmly established when his wife presented him with Clementi's piano music) was his immediate recognition of the depth of keyboard knowledge that Clementi demonstrated in this music, let alone the Romantic prescience made amazingly available when Beethoven was just a lad of about twelve.
It is most interesting to me that although Clementi always spoke glowingly about the music of his younger contemporary Mozart, the veritably total opposite was stated by Mozart, calling Clementi, at one time, a "charlatan," and another time a "mechanicus." Probably in both cases Mozart was citing Clementi's playing, rather than the writings; however, it may be implied that Mozart was wrapping both playing and writing into the same package, as, after all, Clementi was championing his own music by way of performance.
No matter - his playing, his writing, his success as one of the first powerful manufacturers of the piano - this was Clementi.
And yet, we do not hear his greater piano compositions as often as we should.
By the way, one of Clementi's students, who later became one of his chief salesmen in the manufacturing aspect of his career was, arguably, Ireland's most powerful musician. His name- John Field.