You may have heard—as I frequently have—that The
Recognitions is "like James Joyce" or stands out as "the
American Ulysses" or (in the words of Harold Bloom): "The
Recognitions parodies Joyce's Ulysses.” This could hardly
be true, if only because Gaddis hadn't read Ulysses at the time
he wrote his debut novel. "My Joyce is limited to Dubliners and
some of his letters," he admitted to John Seelye in 1962.
Taking place over a short, turbulent period in 1905, 'Petersburg' is a colourful evocation of Russia's capital—a kaleidoscope of images and impressions, an eastern window on the west, a symbol of the ambiguities and paradoxes of the Russian character. History, culture, and politics are blended and juxtaposed; weather reports, current news, fashions and psychology jostle together with people from Petersburg society in an exhilarating search for the identity of a city and, ultimately, Russia itself.
Nice one, that was more what I was looking for...http://gaddis-drinking-club.blogspot.com/2004/11/first-person-to-accost-harold-bloom.html?m=1
Bloom (very briefly) on meeting Gaddis/ "The Recognitions"
Sounds like he was very familiar with the book and read it many times.