The saddest bad relationships are the ones that started out golden.

For years I thought David Mamet was the best playwright in the country. If you asked me, Glengarry Glen Ross was the last word on American capitalism, a scorching, merciless look at what happens when no other ethic has primacy. Speed-the-Plow was a brilliant investigation of the ways our most trusted peers drive us to be worse than we want to be, and Oleanna was a mind-blowing illustration of the infinite interpretability of human action. Even Mamet’s lesser plays, from the gently humorous Duck Variations to the almost-dazzling American Buffalo, had moments of splendor, and the failures — The Woods, The Cryptogram, The Old Neighborhood — were useful experiments in his signature minimalism. This was a playwright on the scent of the truth, and the reports he brought back were always of the highest importance. He never compromised for anyone’s sake, especially not his audience’s.

Then something happened. Maybe it was too much crowd-pleasing work in the movie business, maybe it was artistic exhaustion. But Boston Marriage was a grandiloquent soap opera, a renunciation of his hard-won style, and Romance had so much cheap slapstick, it seemed the work of another writer. For unclear reasons, Mamet was losing his famous grip. If he’d written only plays like these over the years, no one ever would have heard of him.

And now there’s November, the trivial, silly sitcom currently appearing at American Stage.