I believe what is meant by the "magic" in "magical realism" is less concerned with what is included in the realm of possibility and more about the author's sensibility and relationship to her material—invariably that sensibility is acutely playful, ostentatious, and yet curiously self-circumscribed, like a man who puns aloud for his own amusement. Magical realism is a
This lack of systematicity and its consequent enlarged sense of freedom and play is, I believe, what attracts writers to the genre. Writers enjoy writing magical realism because it gives them almost infinite warrant for creativity and yet does not impose upon them the hard work of creating a consistent environment and internal logic for their novel, elements which both realism and SFF demand and require.
However, arbitrariness and ornamentation—the warrant which magical realists enjoy—threaten constantly to wallow in mere frivolousness. The penchant of most magical realism seems to be to toward frivolous and even boring (Rushdie) disengagements with realism rather than meaningful ones. These digressions from the strictures of realism (such as they are—a fraught topic, I know, I know) can at times be pure superfluities, not even advancing the plot or characterization. Such writing does little more than illustrate its status as a created object—a function which has its place, I understand, but which teeters into banality the more that it is used.*
Karen Russell uses her magical realist card almost indecently often, but unlike many others, she does not flash it for pure ostentation; rather, her deployment of magical realist detail is always in the deepest sense necessary—for the plot, for the characterization, for the creation of each story's sensibility and tone. The departures from reality are not used as flourishes which cut away from the meat of the story and of realism itself—the development of a human consciousness at the center of the story—but as the bone supporting that meat and giving it shape. In most cases, one must say that the magic of magical realism is contingent upon its realism—in Russell's case, it is definitively not. Instead, the magic and the realism proceed in step, the development of a human consciousness in these stories growing along with the unfolding of Russell's magical touches, one line of development depending on the other.
Consider "from Children's Reminiscences of the Westward Migration": our growing understanding of the peculiar nature of the narrator's father coincides with our burgeoning sense of the young man as a person, as a consciousness. The same goes for "Z.Z.'s Sleepaway Camp for Disordered Dreamers," "Haunting Olivia," "The City of Shells," "Lady Yeti and the Palace of Artificial Snows," "Accident Brief, Occurrence #00/422" and, to a lesser (or less successful) extent, the title story. (I didn't think the alligator story worked, btw. Sorry.)
Russell uses magic to take us deeper into the shared world of emotion, and particularly those emotions related to family and to childhood. In doing so, she crosses another perilous bridge which has collapsed under a number of contemporary writers (JSF, for one, in his second novel). I don't know how she threads this needle—the only other recent example of a writer depicting childhood so acutely and with such a lack of strain or condescension (to the reader or to the child-character) is David Mitchell in Black Swan Green. However, while BSG is entirely self-constrained in terms of narrative voice by the plausible limits (in diction, sophistication, and observation) of a smart, perceptive, sensitive child, I do not think you can say the same of Russell's stories. No child, no matter how precocious, speaks in the manner in which her narrators indulge. In fact, Russell seems entirely indifferent to considerations of what might be the age-and-character-appropriate articulation of any sight, event, or thought.
However, this lack is, stunningly, an achievement, and not a deficiency. One is compelled by the quality of the prose even as it grows more dubious in its connection to the actualities of the narrator's person or consciousness. It's extraordinary and, at least in my experience, unparalleled in any other contemporary writer. I feel and resent the author speaking over their characters in almost every instance. In Russell, it's an almost welcome fact.
In short, I desperately await Russell's next work—there is so much talent there, I only hope it isn't ruined by the elongation of the novel form.
*Shteyngart's Absurdistan is an excellent example of this phenomenon. Although it is not, strictly speaking, a magical realist novel, its absurdities are so improbable that it might as well be. And now that I think about it, following my musing about allegory and magical realism, its attempt to be in some flabby sense allegorical is quite definitely its major flaw, principally because its absurdities are so ornamental and not structural in any real sense. In contrast, Absurdistan's spiritual fathers, Gogol's Dead Souls and Goncharov's Oblomov, succeed precisely because their departures from probability are completely structural and not in the least ornamental. Don't get me wrong, though—I like Absurdistan a lot, but I do resent its failures.
EDIT: It occurs to me that my remarks about magical realism and allegory seem extremely stupid in consideration of Perfume and The Tin Drum (both German for what it's worth). There are probably a great deal more. Disregard my thoughts, I guess; I just wasn't thinking very hard, it seems.