“YOU CAN’T BE SERIOUS!”That’s what John McEnroe used to scream at linesmen back in the days when he was terrorizing the tennis circuit. His expression of catatonic rage would seem to apply to the present writers’ deadlock. In commencing their final round of talks this week, surely each side is weighing not only the cost of concessions but also the price of failure. On the most basic level, a showbiz shutdown would have a devastating impact on the psyche of the industry and the economy of Southern California. Judging from the impact of previous strikes, a shutdown could permanently shift the balance of television programming from scripted shows to a ceaseless blur of “Datelines” and “Survivors.” This would spell a loss not only for writers and actors, but also for hapless viewers. Finally, the failure of talks would raise serious questions about the credibility of the multinational corporations in managing creative content. The old-line studios and networks presided over generations of relatively peaceful relations with the artists and artisans in their employ. Will Hollywood’s new rulers disrupt this tradition? Considering what’s at stake, the money gap between the two sides isn’t that great. In fact, it’s puny. So maybe we should all plant a loudspeaker outside Writers Guild headquarters blaring the McEnroe message: You can’t be serious! TALK TO THOSE ENMESHED in the negotiations and you’ll get an earful about residuals, double-burst programming and the split of the video pie. The writers will tell you they’re working off anachronistic deals made 20 years ago. The studios will tell you they’re poised on the brink of financial ruin. You can’t be serious! The overview comes down to this: The creative community takes a look across the table and sees not Barry Meyer or Bob Iger, but rather the specter of AOL Time Warner and Vivendi Universal and News Corp. The studios may plead that their profits are wafer-thin — wafers seem to enter their vocabulary a lot these days — but top writers and movie stars want “profits” defined in a broader context. The production entities, after all, are now minor cogs controlled by distribution companies with global tentacles. What once was a movie or TV show now is a particle of content that will tap into myriad revenue streams and ultimately disappear into vast libraries of ever-growing value. Hence the ultimate standoff: The top creative talent used to believe they owned a share of what they produced. Today they feel they’re becoming hired hands. If this conflict sounds esoteric, the impact is anything but. Showbiz pumps some $31 billion into the Los Angeles economy each year. The industry directly employs 255,000 people, with another 212,000 laboring in industries linked to production, such as wardrobe and catering, and tens of thousands more who work in restaurants, the limo business and other peripheral trades. A SHORT STRIKE WOULD PUT a small dent in the economy, but no one thinks a strike will be short. Given the egos and issues involved, a shutdown surely would drag on for many months, and it’s the little guy who will be hurt the most. By the time it’s over, a lot of homes will be foreclosed and a lot of TV viewers will be conditioned to accept a whole new range of entertainment. While both sides this week may quarrel about numbers, the community must demand that, at some point, the rhetoric will cease and pragmatism prevail. If the writers can’t make a deal, it’s hard to believe the disheveled Screen Actors Guild can make one. They can’t even figure out how to coexist with their own agents. Are the writers and actors ready to shut down Hollywood? You can’t be serious!