Last week, in California, a group of experts sat around a table in a corner booth and once again debated the question: Who produced Shakespeare? We all know who wrote Shakespeare. It was someone named "Shakespeare." But who was the producer? Who was the genius behind the Bard? The ages-old mystery may never be solved, but everyone has an opinion.
   ICM's Sam Mintz, who represents Loretta Swit, among others, thinks it was the Earl of Oxford.
   "Just a hunch," explained Mintz as he measured his first bite of an overstuffed corned beef sandwich. "He had the education, a lot of confidence, and the pocket change to back it up. Look at the long run this guy's had."
   "Christopher Marlowe," opined Larry Blamen, the 23-year old whiz kid programmer at Fox. "Look at the folios," he mumbled between spoonfuls of cream of barley soup.
   No less an authority than Prof. Gary Taylor of Ohio State University, co-editor of the most recent (and most controversial) edition of the complete works of Shakespeare, was not invited. However, Warners publicist Marty Bimmerman, munching on an English muffin, pushed the "husband-and-wife team" theory.
   "I see a team like Barbara Corday and Barney Rosenzweig, or maybe even a Paul Newman-Joanne Woodward kind of thing. Look at 'Taming of the Shrew.'"
   Prof. Lawrence McVay of Columbia University, a Shakespearean scholar and noted lecturer, pointed out that the status of women in Elizabethan times would have "precluded their involvement in such a business." He also had the corned beef.
   Debate, most of it friendly, went on for hours. There were supporters of Francis Bacon, backers of Ben Jonson, and one, Sid Klopman, ABC's West Coast V.P. in charge of Music/Variety Specials, who thought that Shakespeare himself may have been involved.
   "You know, a guy who could work on both sides of the camera. Like a Jerry Lewis."
   In the end, of course, no conclusion could be reached. As Barry Tedesco ("Good Morning, America") said while they figured out the check: "It's hard enough remembering what happened last week, let alone three hundred and fifty years ago."