Every new movie by America’s only blockbuster documentarian confronts the fence-sitting viewer (if any are left) with the same choice: the Michael Moore you came to see, and the Michael Moore you get. The ideal Moore promised to take aim at the unseemly aspects of the country’s gun culture; the actual Moore of “Bowling for Columbine” ended up stalking Charlton Heston with the photo of a gunned-down girl. The ideal Moore tried to expose the shortcomings of our post-September 11th policy making; the real Moore of “Fahrenheit 9/11” nonsensically deployed Iraqi children to romp gaily under Saddam Hussein’s rule.

It’s the difference between making a coherent, factually rigorous argument and pitching straight to the gut with whatever mode of manipulation is handiest. On its face, “Sicko,” Mr. Moore’s latest attempt to tackle a massive, fraught sociopolitical issue, looks especially vulnerable to the filmmaker’s rabble-rousing tendencies. Like guns or war, health care is a life-and-death issue, and there’s no shortage of personal horror stories about America’s overburdened system.

Yet like so much of Mr. Moore’s work, “Sicko” is most healthily taken as a satirical polemic, not an airtight policy proposal. Mr. Moore’s screed wallows in pitiable anecdotes, cherry-picks history, and applies skepticism selectively as suits its arguments. But as the filmic equivalent of a shameless and sardonic dinner-table raconteur, “Sicko” at its best rocks more like Twain than Chomsky, stringing together a story that begs to be retold.

Mr. Moore’s solution to the health care crisis is avowedly simplistic, much like the diagram structure of his film. First come a litany of denied-treatment casualties and an origin story for the HMO behemoths in President Nixon’s market-friendly reforms of the early 1970s. Then Mr. Moore whisks us away with his satirical centerpiece: a borderline Swiftian travelogue to the cats-and-dogs-living-together world of heavily insured foreign lands.

The hale and hearty inhabitants of Canada, England, and France all chortle at the very idea of paying for medical treatment. They’re showered in free treatments and prescription drugs, cushioned by all manner of medical leave, and yet able to keep their government doctors in Audis and condos. Mr. Moore wonders aloud if the government even does a Frenchman’s laundry; it does (as part of maternity care). Oh, why can’t we just switch and be like them?

Like the lifestyle pitch of a good advertisement, this is hard to resist. It’s entertaining, sounds like common sense, and makes a great pseudo-cosmopolitan story to tell at barbecues. It’s also comforting to imagine the possibility of successful reform — without ever really learning the nitty-gritty of how these systems are sustained.

But the reason we can’t switch health care systems, according to the subsequent visual logic of “Sicko,” is that homeless men and women in Los Angeles who can’t pay hospital bills are stuffed into taxis and dumped downtown.

Come again? Let me explain: In a move that is typical of his relentless emotional pivots and feints, the very next item to follow Mr. Moore’s account of la belle France is the story of a “dumped” homeless woman, complete with excruciating surveillance camera footage showing her wandering dazed in black-and-white silence. “Who are we?” to do this, Mr. Moore muses, having paired America’s most abused with the uncritically viewed utopias of other nations.

This is the pontificating, tear-twinkling-in-one-eye side of Mr. Moore that is so hard to bear or believe, even when you sympathize with the people he depicts. In his smarmy approximation of empathic newsmagazine voice-over, he narrates tale after tale of woe, and yes, this is all terrible stuff: a hospital turning away a feverish baby to die, an HMO essentially running out the clock on a man with a serious kidney condition, and endless other evasions of payment and treatment.

But for a man so skilled at manipulation, Mr. Moore can be astonishingly tone-deaf rhetorically, piling on worthy stories as if more is better. His strongest weapon has always been the ordinary people willing to act as his human-interest cruise missiles, full of bluff American humor and resilience. Yet the extent of his pimping people’s pain in “Sicko” recalls the 2000 “Saturday Night Live” parody of candidate Al Gore advancing health care examples at the presidential debates: “Just last week Etta Munsen woke from a coma to find that, due to a hospital mix-up, her left arm had been amputated, infected with syphilis, and then reattached …”

If the awful truth of Real Moore is too much to bear, it’s worth recognizing his satirical agility. For example, he deflates former Louisiana Congressman Billy Tauzin with a simple, ridiculous montage of the politician’s mawkish congressional speeches about loving his mother. The antic gesture twists the knife just as sharply as the plain facts at hand, namely Mr. Tauzin’s move from regulating the pharmaceutical industry to banking millions as its chief lobbyist.

In this light, the film’s climax — Mr. Moore’s infamous transport of ailing World Trade Center rescue workers to Guantanamo Bay and then Cuba proper for superior medical treatment — becomes more than just a grandstanding stunt. Beyond the lame political theater (and the carefully stage-managed press leaks since the event), there’s a bracing perversity to this dark bit of satire that’s hard not to admire. Mr. Moore’s sentimental pandering borrows directly from the playbook of politicians themselves, but the ragged edge to his agitprop humor is his own as a hands-on pundit, cursing and criticizing in the same breath.

Though nowhere near as incendiary as “Fahrenheit 9/11,” “Sicko” confirms Mr. Moore as a film essayist of more than respectable talent, if not always a respectable polemical foe. For all the eye-catching editing montages that draw you in, his range of appeal remains constrained: Anyone who features die-hard English socialist Tony Benn and Che Guevara’s daughter as talking heads can’t be fooling himself about the political makeup of his audience. And his habit of persuasion by omission ironically sabotages anyone who actually adopts the film’s talking points without filling in the gaps. (Cuba’s health care comes at the price of other freedoms, for example, and all those happily socialized Frenchmen have just elected the liberal market reformer Nicolas Sarkozy. And so on.)

In choosing the health care system, widely agreed to be in need of overhaul, or at least remodeling, Mr. Moore again finds a grand stage for dramatizing his old hobbyhorses: the points of grinding friction between humans and the hard numbers of economics, the fault logic in our vaunted social systems, and the dignity of the little guy. It’s a “soft” level of appeal, but whatever the execution, these are all undeniably the classically resonant themes of an effective gadfly satirist who alternates between blunt and very, very sharp instruments.

But in his execution and his favoring of tugging at heartstrings over accounting for purse strings, Mr. Moore is, in short, a perfect match for the calculation and sentiment of the politicians he decries.