Those were my two likeliest answers when, upon finishing Robert McKee's Story, I asked myself why anyone would fork over hundreds of dollars to attend one of McKee's screenwriting seminars when they can read this book, which appears to be a transcript of the seminar, for a relatively paltry twenty-five bucks.
Alas, the price still isn't right. (If you must read Story, borrow a library copy. That way, you'll only waste time.) While reading this Holy Scripture of McKee's weird screenwriting cult (so ably and deservedly satirized by Charlie Kaufman in the film Adaptation), I frequently broke into laughter at the author's odd combination of ignorance and grandiosity. He presents himself as an oracle communicating the supersensible secrets of the Platonic Form of 'Story,' but his knowledge doesn't extend to any narrative or literary or film theory of the last 50 years, and the few outdated notions he has gleaned from Aristotle, early Wayne Booth and a few others are treated with risible ahistoricism. His embrace of a ridiculously hardline formalism, along with a distaste for any mention of politics in reference to art, leads to an untenable formalist essentialism that he attempts to support with weak ad verecundiam arguments. Granted, these are theoretical issues, and McKee is on somewhat firmer ground when he turns to the craft of screenwriting, presenting detailed analyses of scenes from films as diverse as Casablanca, Chinatown and Through a Glass Darkly. But even his discussions of craft are marred by arbitrary prescriptions (against voice-over, for example) that simple-mindedly elevate McKee's personal preferences into artistic laws. (We're lucky that Jules and Jim and Goodfellas were in the can long before Truffaut and Scorsese could 'benefit' from Platonic Bob's infinite wisdom.) Since this book isn't worth any more of my time, I'll end by quoting Gore Vidal quoting an old Hollywood screenwriter he called the Wise Hack: "Shit has its own integrity." McKee's book is an odorous monument to this notion, and my best response to it was written many years ago by ee cummings: "There is some shit I will not eat."
Postscript: The worse news is that Blake Snyder's even more influential Save the Cat! screenwriting education franchise makes McKee's look positively highbrow. With gurus like these forming our nextgen moviemakers, we can expect no end of formulaic feces from the Hollywood pipeline.