How Alice Munro takes on the most tired of narrative cliches - and writes a great story

Anyone who's ever read through the "slush pile" (which I do not disparage - said pile has been my only point of entry for all my publications) for a magazine or for a short-contest knows that you will repeatedly come across certain tropes, perhaps the most common and and annoying of all being: and I woke up and it was all a dream! That format is an easy way for a writer to get away with any sort of ludicrous, bizarre, impenetrable material in the narrative and then - to the reader's supposed surprise - explain it all away as a dreamscape; or, another variant, to build up a really tense situation - a crime or horror scene, pursuit, et al. - and then rather than concluding with any dramatic or satisfactory resolution, snap, you wake up - and sometimes, in the weakest of these stories, the events begin again in waking life. Okay, so why is Alice Munro working this most hoary of tropes in her story In Sight of the Lake, in her latest collection, Dear Life? The only reason she would take this on would be to write the definitive dream-awakening story, and of course she nearly does so. Sorry to be giving away spoilers here, but it does take a while for readers to realize that we're reading some kind of dream narrative, because Munro is able to keep her narrative just on the edge of plausibility. Briefly, the story, in first-person narration, is about a 70ish woman who sees her doctor to discuss recent loss of memory and he recommends she see a specialist in a nearby town; she drives to the town and has trouble locating the office. This behavior is possible because the very essence of the story is that the woman is losing her short-term memory and behaving oddly in other ways as well - but gradually, eventually, we begin to sense that it's not her behavior only that's out of alignment: for example, does it make any sense that she would drive alone to this town the day before her appointment and stay over night? At first, I thought this was a fault of the narrative, but began to realize it was the point of the narrative; similarly, she sits down in a private garden, and the owner escorts her on a walk through town looking for the office - again, almost possible, but not quite, a little bit off - and we sense that this dream is a retelling, in a new form, of the entire course of this woman's life, ending, as it does, in a nursing home with locked door. It's a nearly perfect story, but I will have the temerity to offer a suggestion (when I was in the great writing group in Providence, PAWs, we used to pride ourselves on our critical approach to one another's stories and probably to everything, Shakespeare, Aeschylus, you name it): why the last short section in which the narrator does wake up, in presence of her nursing aides? I'd say just end it when she's locked in the nursing home - leave it slightly open and ambiguous - Munro's readers, educated in her style, will get it.