"Boston Marriage" had him trying his hand at drawing room comedy; "November" found him recycling farcical shtick from the trunk of George S. Kaufman. Mamet has even adapted Harley Granville Barker's "The Voysey Inheritance" for the stage and Terence Rattigan's "The Winslow Boy" for the screen — two English playwrights whose decorous manners wouldn't seem an obvious draw for an American dramatist who strings four-letter epithets with all the insouciance of a rap star.

His wide-ranging film work (he wrote and directed the oddball comedy "State and Main" and co-wrote the Oscar-nominated screenplay "Wag the Dog," among other credits) has no doubt encouraged this adventurous streak. But in the theater these explorations inevitably seem like diversions from the main act, as though the author were taking a holiday from his combustible sensibility. Mamet has a patented flair for comedy. Yet neither "Romance," with its kangaroo courtroom antics, nor "Keep Your Pantheon," with its ancient Roman horseplay, amounts to much more than a cocktail napkin doodle.

Yet his ire is clearly no longer serving as a reliable muse. (Retrospection might be more fruitful, as "The Cryptogram" and "The Old Neighborhood," perhaps the second best work in his post-"Oleanna" period, suggest.) In his younger days, Mamet turned con men into feisty symbols of the fiasco of American capitalism. Now an unregenerate capitalist himself, he's been on the hunt for all those have-nots eager to pick his pocket with their outlandish demands for justice, equality and fairness.

There are no good guys in Mamet's plays, but it's possible to tell where his sympathies are through glimpses of what lies behind the mask of his sneakier operators. In "The Anarchist," which revolves around the parole decision of a convict associated with a radical Weather Underground-like movement, the details that emerge about the prisoner only tautologically confirm the foolishness of second chances for those who don't deserve them in the first place.

Funny, isn't it, how a play can conclusively prove the truth of its playwright's bias? Funny for anyone, that is, not paying an arm and a leg to see LuPone and Winger try to breathe life into lines only a typewriter could pronounce.

Some might argue that Mamet is providing a useful service, challenging articles of liberal faith from inside the elitist stronghold. But his contrarian streak, once the source of his independent vision, has become all too predictable. There's nothing especially radical in siding with power over those seeking restitution for their lack of it.

Writing at the highest level requires an "incandescent" imagination, one unencumbered by too much anger or bitterness, as Virginia Woolf argues in "A Room of One's Own" — a book not likely to be among his dog-eared college favorites.

Mamet has been using the bully pulpit granted to him as an artist to broadcast the doctrines of loudmouth talk radio, that boisterous realm in which innuendo substitutes for evidence and fear-mongering replaces analysis. That's his prerogative as a citizen. But what a shame for progressives and conservatives alike that such a gifted dramatist has allowed his hotheaded dogmas to ruin his art.