Such a no-count, lovely piece of ground! I love that line. It’s an epiphany. It perfectly expresses a key element of Frazier’s governing aesthetic – his eye for the overlooked and the disregarded. We wouldn’t have the benefit of this sudden insight, except that Frazier decided to take a side-trip to the Rijksmuseum and to write up his experience and include it in his piece on the Strandbeests. Does Frazier’s digression make his piece “baggy”? Not in the eyes of this beholder. It makes it a great essay. Adam Phillips, in his Side Effects (2006), says, “The literary essay as a form – at least from the early nineteenth century onwards – has not only allowed for the artfulness, the interest of digression, but has also positively encouraged it.” I rest may case.
Postscript: There’s one sense, of course, in which Frazier is a baggy writer. He’s obsessed with bags in trees. See his classic “Bags in Trees” trilogy (in his 2005 collection Gone to New York) and his recent "The Bag Bill" (The New Yorker, May 2, 2016). But this clearly isn’t what Rotella is referring to.