OPEN-MIC NIGHT at the local comedy club tends to be painful. An open mic on cable news, however, can be illuminating, revealing a trait talking heads share with reality TV contestants — a willingness to do whatever’s necessary to justify their exposure.

Among the political punditocracy, the underlying mindset seems clear: We know what we must say to fulfill our predefined roles and put on an entertaining show. So if you’re looking for an honest discussion, keep in mind the “The Wizard of Oz’s” admonition “Pay no attention to that man behind the curtain,” or more appropriately, “Pay no mind to those strident bozos before the cameras.”

The most recent slip came on MSNBC, where Wall Street Journal columnist Peggy Noonan and Republican strategist Mike Murphy could be heard after their televised chat ridiculing GOP nominee John McCain’s selection of Sarah Palin as his running mate. In the case of Noonan, whose columns frequently express misty-eyed longing for a return to Reagan’s America, it was rather refreshing to hear the phrase “political bullshit” trip off her tongue.

Still, it’s not like Republicans have a monopoly on such gaffes, lest anyone forget Jesse Jackson’s open-mic broadside on Fox News about neutering Democratic standard-bearer Barack Obama.

Those, moreover, are the seasoned pros — the ones that shouldn’t hunger quite so eagerly for the approbation of cable news producers. Imagine how pliant must be the army of “strategists” that cable networks churn out faster than Nintendo can manufacture Wii consoles. Whenever possible they are young, attractive and (to balance the existing gender gap among hosts) female, bearing the imprimatur of some official-sounding group. Invariably, they seem happy to argue the “con” to any “pro” — just short of insisting Hitler really wasn’t such a bad guy and his “solution” wasn’t all that final.

SMALL WONDER that MSNBC’s resident inhouse conservative, Pat Buchanan, occasionally loses his cool jousting with someone who wasn’t even a dirty thought back when he carried water for Richard Nixon. Not long ago he snapped at Keli Goff (surely you’ve heard of her; she’s a “Democratic strategist”) to “shut up” when she interrupted him; yes, the eruption was certainly rude, but it made for a great YouTube clip.

The way cable’s drone army hits their marks and speaks their lines has much in common with the made-by-TV stars of MTV’s “The Hills” or Bravo’s “Date My Ex: Jo and Slade,” which bears a disclaimer acknowledging that portions have been “arranged and edited for dramatic effect.” A purist might refer to such sleight of hand as “acting,” but the manipulation of reality to heighten drama isn’t a huge leap from the verbal pugilism on “Hannity & Colmes.”

From personal experience, news bookers aren’t bashful about indicating which side of an argument they need you to take — in essence saying, “If you want to be included, please articulate this opinion.” Should that coincide with what you truly believe, all the better, but genuine conviction in what you say is hardly a prerequisite. (Remember, for example, right-wing radio host Kevin James passionately calling Obama an “appeaser,” only to be exposed by MSNBC’s Chris Matthews as having no idea what “appeasement” actually meant in historical terms.)

RECENT OPEN-MIC snafus similarly feed the impression that the real unvarnished debate is occurring off-screen, a revolution untelevised. Moments of candor are so rare that Bill Maher’s HBO gabfest “Real Time” stands out, despite its shrill tone and heavily stacking the deck against conservatives. At least the series benefits from the blunt, unfiltered exchanges elicited by the pugnacity of its host.

On Huffington Post this week, Vermont Sen. Bernie Sanders, the longest-serving independent member of Congress, pleaded not to let campaign coverage “descend into becoming a pre-game football show,” reminding networks that elections are more than just “soap operas for political junkies.” He’s certainly diagnosed the problem, but that alone won’t help differentiate the stats and analysis on “Race For the White House” from “Fox NFL Sunday.”

There’s nothing wrong with developing commentators that go beyond rounding up the usual suspects. Yet turn down the volume enough to hear the emptiness of their rhetoric, and unlike most comedy showcases, you just might laugh until you cry.