Hollywood movies spoofing Hollywood are amusing only if viewers have an inkling of how the business works; the pecking-order insecurities, the justification of pandering for profit, the conspiratorial disdain for junk-flick audiences and camouflaging hype. I have a pretty good idea yet something like William H. Macy's The Deal still can turn me off for being too "inside."

Audiences agree, judging by embarrassing box office results for most modern Hollywood-themed movies: America's Sweethearts (despite Julia Roberts, Billy Crystal, Catherine Zeta-Jones and John Cusack), James L. Brooks' I'll Do Anything, Tim Burton's Ed Wood, and An Alan Smithee Film: Burn Hollywood Burn among the most notorious.

What those flops didn't have -- and the new comedy Tropic Thunder revels in -- is carpet-bombed profanity, gruesomely violent scenes (staged and real), and jokes about sex, race and mental retardation that are guaranteed to offend somebody. And farts. Lots of farts.

That's what sells movie comedies these days. Tropic Thunder will sell a lot of tickets when it opens in theaters Aug. 13.

Yet, director/co-writer Ben Stiller gets caught in the same self-mockery trap of those previous Hollywood satires, too focused on jokes about actors, agents and studio chiefs that wouldn't mean much to viewers if they weren't presented by Robert Downey Jr., Jack Black, Matthew McConaughey and Tom Cruise. The stereotypes aren't even fresh, although such star power will attract moviegoers who wouldn't go near Woody Allen's Hollywood Ending, The Big Picture or Swimming with Sharks. They may be impressed.

Did I laugh? Occasionally, when an obscene euphemism or shock joke hit home. Downey''s portrayal of an Australian multi-Oscar winner whose Method obsession leads to "pigmentation alteration" to play an African-American soldier in a war movie is funnier when a genuinely black actor (Brandon T. Jackson) is calling his bluff. Cruise is obviously having fun sending up Hollywood producers, with bald head and extremely foul mouth.

But the advance buzz for those actors originated in L.A. where their inside jokes play better. That's why Stiller's immersion in raunch and exaggerated gore feels cheap; he knows what the yokels will "get," even if it isn't what he and the guys are laughing about while watching daillies. There's a whiff of arrogance to Tropic Thunder, unlike Hot Fuzz which successfully spoofed action flicks by focusing on what makes them appealing to the masses.

The real audience for Tropic Thunder will see it for free at red carpet premieres and industry screenings.  Everyone else will have to buy a ticket, but aren't likely to make it "inside."