Stephen E. Bacher replies to me:

>>In the last movement, Shapero makes his intent plain with an unmistakable
>>shard of Beethoven's Seventh, which he nevertheless integrates into the
>>movement itself - a surprise, but not a surprise.  Suddenly, the previous
>>movements come into sharp focus, and you marvel at how something so
>>original owes so much to its predecessor.
>
>Something very similar is done by Sir Michael Tippett in his Third
>Symphony with its use of Beethoven's Ninth.

I would say that the Shapero differs from Tippett in that Tippett is
using the Ninth in a more "localized" and even usual way -- first of
all, as an icon, which he nevertheless does integrate into the movement.
Ives does something similar (though even more localized) in the Concord
Sonata with the Beethoven Fifth.  On the other hand, in the Shapero,
the fragment of the Seventh opens up the entire symphony, not just one
movement.  It comes across as a revelation, a key to some of what's been
happening since the opening bars of the entire work.

Steve Schwartz