A coming-of-age novel that maybe should have been written as a memoir

The recently deceased William McPherson was a Pulitzer Prize winning book critic for the Washington Post in the 1970s and 80s (I'd met him once or twice but can't say that we really knew each other); his obituaries, in telling his strange life story - he gave up his newspaper job and spent much of his later life in abject poverty - were glowing in retrospective praise for his (first?) novel, Testing the Current. Looking back at this coming-of-age novel, it seems a little dated, maybe even dated at the time of publication (1984 I think): not only its era-typical title (verbing the noun) and its ugly cover design but in the whole conception of the book: it's a long (350 pages, small type) account of a young man's recollection of his youth in a prosperous Michigan industrial town, life centering on "The Island" where all the well-to-do families "summered" and on the young boy's fascination with his much older siblings and their love lives and the many rumors and histories of other families in the town and on The Island. It's a totally WASP, Republican (and anti-Roosevelt) world, with country clubs and golf at the heart of the matter and with the assumption that all the children will go to "good" schools and will marry w/in their social set. The central character, Tommy, is part of the long line of sensitive young men somewhat adrift in a world of society, sports, and business. It's a little strange that McPherson wrote this novel in the 3rd person; it would have felt to me much more authentic in the first person, as an adult writer reflecting back on his youth - in the manner of Proust, obviously (though I would not say this novel is Proustian) or today's Knausgaard. Alternatively, McPherson could have written a memoir - but he was just ahead of the curve. In the mid-80s the memoir suddenly was in vogue, especially in the idea that the memoirist need not be famous nor to have suffered grievous hardship but must be only a fine writer. I suspect that had he embarked on this project 10 years later he would have written a memoir and not a novel, and that would have helped, would have given the work an urgency and an authenticity that it needs; as a novel it's, so far, abundant in period detail, many descriptions of the decor, the dress, the cuisine of the era and the class - but devoid of what makes Proust so great. We don't get meditations on the past, we don't get a sense of why the writer is driven to recollect past events (or can't help himself but recollect them), there's a ton of detail (any editor today would say too much detail, cut this by half at least) w/, so far (1/3 through) no plot or narrative to advance - it's detail for its own sake (to create a sense of time and place I guess), and there are far too many characters, seen from Tommy's 8-year-old (though precocious) POV, none of whom really mean anything to us nor to the narrative. Yet something draws me in and along - the novel is an attempt to look at a past time and now, 30 years after publication, it's a timepiece in itself.