I agree with The New York Review of Books, that William Gass's Middle C is an antidote to his earlier book, The Tunnel. Gass's latest is much easier and more enjoyable to read, though it is not more accomplished than that previous work, unless lightness can be counted as an accomplishment.
I have long been a fan of William Gass, ever since I read Omensetter's Luck while acting as fisheries observer on the docks of Prince Rupert and Port Edward, BC. He is called by most a postmodernist, but as with the best of that so called lot, he defies easy categorisation. To lump Robert Coover and William Gass together is like putting two cats in a bag. They don't mix, get along, act in tandem, or resonate except as two exemplars of general cat-ness that need room to breath, roam, and relax into their natural tendencies. Both Gass and Coover, for example, use language in a breathtaking way to tell stories of great depth, playfulness, and expansiveness. It is this 'use' of language that binds them, if in any way they can be said to be bound. Both are masters of the craft of storytelling that goes back to Moby Dick.
Middle C is about more than language though. Language is the medium through which something more important is explored: music. Music speaks of things in a way no words can convey. But music and language act together. Music, at a 'meta' level, is a kind of language. Both are memetic. Stephen Jan's The Memetics of Music explains very convincingly connections between music and (cultural) evolution. Marion Blute's Darwinian Sociocultural Evolution includes sections that do the same thing for language. The beauty of Middle C is, first that shows, rather than tells (i.e. in academic language), us that music and language share a common cultural evolutionary equivalent in the meme. Second, it weaves language and music together so beautifully.
When I read Gass I think less of postmodernism or memetics, and more about James Joyce, myths, archetypes, and stereotypes. The psychological depth of understanding of the main character's split/dual personality Joseph/Joey Skizzen (which means sketch), and the intergenerational trauma from which it stems is, quite simply put, staggering. Identity is explored from the perspective of a non-Jewish family escaping Nazi Vienna by pretending to be Jewish, a lifelong pretense that stuck. The trait of lying was so well developed in Joey Skizzen that he perfected its art, reinventing a life that excluded the fleeing incident, replacing it, instead with a fictitious life of a well-heeled Viennese bourgeois who immigrated to America to escape persecution based upon his (fictitious) Jewishness. The conceit that drives Gass's story is so outrageous and all the more so because it works so well.
Professor Joseph Skizzen is, then, a 'real' fake, one who has had to work hard to undo a devastating legacy of harm instilled by his parents. Abandoned by his father, Joseph lives with his mother throughout a life lived in a small midwestern town described by Gass (who was born in Fargo North Dakota) in gorgeous detail. I've heard Gass's work described as 'moral fiction,' and indeed it is. There is something very edifying in this work that includes, at the same time, as another of its central conceits, something called the Museum of Inhumanity. This is Joseph Skizzen's incredibly autodidactic (for that is what, at base, he is: an a cranky self-taught fraud) collection of books and newspaper clippings 'documenting' through accumulation (rather than selection) horrible things one segment of humanity has inflicted upon another. How all this adds up to an incredible feast of a book that was, for me, a page turning thriller, I leave up to other readers to decide. I don't try to question the magic or the method of Gass.