From Ives Wins!, I liked this bit (my bold):
If Ives’s music often falls flat in performance, does that make the music less great? For most people the answer is unequivocally yes. But it’s worth contemplating the example of three piano sonatas, all written within fifteen years of the premiere of Ives’s “Concord,” by three of the most important American composers: Carter, Barber, Copland. Each of these pieces attempts an epic statement, fusing popular music with the complexities of modernism. Each is more expertly composed than the “Concord”—better crafted, more transparent, more pianistic—and eminently practical in concert. But Ives’s sonata towers over them all, despite or because of its doubts, sweeping past the fine points of constructing a musical work to address the nature and purpose of music itself. And that is the injustice of art; sometimes all the craft in the world is trumped by someone with something more important to say.