The sad, surprising part of all this is that those five shows, in any of the combinations that NBC has tinkered with this season, make up the strongest comedy slate on television today. Furthermore, the current Thursday night lineup may comprise the NBC's best set of Thursday comedies in 30 years, when The Cosby Show, Family Ties, Cheers, and Night Court first appeared under the "Must See TV" branding. That's no small praise considering Thursday nights have been home to some stellar combinations that included the likes of Seinfeld, Mad About You, Frasier, Friends, Will and Grace, and Scrubs.

Not only were all of those NBC comedies critical favorites, they were huge hits, ranking among the top-rated sitcoms on TV when they aired. The perplexing thing about NBC's current Thursday lineup is that—even though TV ratings are down across the board due to audience fragmenting, TiVo, the rise of cable, and a laundry list of other reasons—they are also poorly rated when compared to other shows currently on rival networks. Hit shows like 2 Broke Girls and The Big Bang Theory that are not as well-reviewed as the NBC comedies earn 16 million and 10 million viewers each week, respectively. Why can't NBC turn its critically beloved comedies into the outsized hits that their Thursday night predecessors once were, and less-than-stellar present competition currently are?

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Perhaps the biggest barrier is their uniqueness. Community, with its meta recasting of B-movie genres, tangled web of self-referential dialogue, and litany of nuanced pop culture references, does not have the same broad appeal of Charlie-Sheen-cum-Ashton-Kutcher telling sex jokes while a boarish teen actor farts in response. The telegraphed punch lines, laugh tracks, and self-contained plots of a show like The Big Bang Theory carry a comfort-food allure that 30 Rock, with its inside-baseball humor about Comcast's corporate woes, doesn't offer. Anyone who regularly watches Parks and Recreation can attest to the smart, creative, and progressive humor the show offers, but a series like How I Met Your Mother is more popular because it's easier to watch, and easier to laugh at.

A look back at the NBC classics—Friends, Will and Grace, Frasier—reveals more in common not in content, but in format execution with series like Two and a Half Men than with single-camera mockumentaries like The Office or Parks and Rec. They were colorful, multi-camera sitcoms with laugh tracks, that, though more smartly written, relied just as much on ba-da-DUM joke set-ups as Men or Broke Girls do.

With all the red roses currently being enthusiastically tossed at NBC's Thursday comedies by critics, it's also easy to forget that these shows weren't always so good. In some cases, they even started out terribly. In Bossypants, Tina Fey writes that she's so openly embarrassed by the pilot for 30 Rock that the show's writers had to ask her to stop dissing it so brutally. But Fey is correct; the show 30 Rock started as is lightyears away from the one it grew to be. It wasn't until about the seventh or eighth episode of season one, when the show's running jokes (The Beeper King, The Rural Juror) started to take off, supporting characters like Tracy and Kenneth settled into their quirky personalities, and Alec Baldwin's one-liners grew more and more outlandish that the show turned around. Similarly, Community debuted to mixed reviews, before finding its one-of-a-kind, almost indescribable comedic voice roughly midway through its first season. It took longer than that for Parks and Recreation to gather its footing. Its entire first season was widely panned as an egregiously unfunny Office copycat, until Amy Poehler developed Leslie Knope into tempered a loopy lead character with a warm groundedness that starkly differed from The Office's Michael Scott. Parks's rapturously reviewed second season is considered to be one of the greatest sitcom turnarounds in recent years.