Somewhere on the campus of Sierra College there is a grassy knoll. I haven't found it yet, but there's always one in situations like this.

Controversy has disrupted this quiet town 25 miles north of Sacramento, where the San Francisco 49ers prepare for the football season. In the 7-Elevens and Burger Kings, in the auto garages and hardware stores, people are choosing up sides.Steve or Joe? Joe or Steve?

The Great Quarterback Controversy. It has taken on a life of its own, like a drop of plasma that grows into the Blob that ate Akron. The unrest it has created, the fear even - will the Quarterback Controversy hurt the team? - calls for a thorough and cool-headed examination of the situation.

First, you must dismiss the fact that an actual controversy exists. It doesn't. Joe Montana is the 49ers starting quarterback. He is coming off his best season ever. He won his first NFL passing title in his nine-year career. He set a team record and led the league with 31 touchdowns. He set an NFL record with 22 consecutive completions.

He has led the 49ers to two Super Bowl victories and was voted Most Valuable Player in both.

He is just 32 years old.

Steve Young, the backup, is a brilliant athlete, no question. Quick, gutsy, smart. He can run as well as any quarterback in the league, and he needs to. Running has become a survival tactic because he doesn't see the field yet. He can't pick up secondary and tertiary receivers and until he can, he can't match Montana.

So with that out of the way, the question is: Why does there SEEM to be a quarterback controversy?

The source of the furor is easily traced. Since the playoff loss to Minnesota last December, one person has single-handedly kept the controversy alive. He is the 49ers' own Wizard of Oz, standing behind a curtain, pulling all the knobs and pushing all the buttons, orchestrating the situation.

When asked an open-ended question about the top priorities of the team on national television last week, the first thing coach Bill Walsh mentioned was the quarterback controversy.

When he held his first press conference since returning from London this week, Walsh spent 20 minutes talking about the controversy. He didn't clear it up; he deepened it.

Why is he directing this theater of the absurd? There are several theories.

One is that he is showing everybody, and especially his star player, that even if the owner has taken away his title of president this year, he is still in charge. He, and nobody else, will decide who will start.

Another theory is that Walsh is fueling the controversy as a way of tweaking Montana, who has had his differences over the years with Walsh and who candidly wrote about those differences in his autobiography two years ago.