To the baseball and football fan with a mind, the last few years have been fascinating. Dozens of baseball players have increased their income geometrically by playing out their options and switching teams. But free agency for football players has been like running through molasses -- no movement.

"Prosperity is killing us," said the executive director of the NFL Players Association, Ed Garvey, who thought the agreement signed three years ago after so much acrimony would be fair to both owners and players. He was wrong.

At the moment, about 140 players -- some of them quite good -- are dickering with other teams. If the two-year history of such bargaining holds, no more than a dozen will receive offers and nobody of consequence will change teams.

There are several important reasons why football owners are less anxious than baseball owners to bid for players of almost equal talent, why Too Tall Jones is less likely to leave Dallas than Pete Rose was to leave Cincinnati.

Two of the reasons are a coach, George Allen, and a judge, Earl Larson. The others are economic, although Garvey suspects the owners of being unfair. Because there has been no widespread cheating, he says, there must be a coverup.

But that last bit of logic, which helps form Garvey's hypothesis and might well develop into a law of pro sport, follows the basic fact that baseball owners are more attracted to free agents because they have seats to sell.

"George Steinbrenner doesn't play to capacity each game, so he knows the Reggie Jacksons will pay for themselves by bringing in more fans -- and through local TV," Garvey said. "Same thing with the Phils and Pete Rose.

"But the pro football teams have no economic returns like that. The television money is guaranteed and so are the gates, because nearly every team plays to a full house.So even if the Redskins signed Earl Campbell they couldn't gain financially. There'd only be an outflow."

Also, teams are notorious copycats. And the only Super Bowl winners have been teams devoted to the conventional way of using the draft. Allen tried the reverse method -- trading future choices for proven players -- and the Redskins kept sliding after losing to Miami in Super Bowl VII.

Allen even had the benefit of the baseball-like situation of no compensation in 1976. He signed Calvin Hill, John Riggins and Jean Fugett -- and the Redskins did improve their regular-season record by two games. But they lost in the first round of the play-offs.

With the spectacular recent success of the Steelers and Cowboys and the rise and fall of the Redskins, teams have been cautious about parting with high draft choices. The only significant free-agent signing has been Norm Thompson, signed by the Colts at the cost of a third-round draft choice to compensate St. Louis.

The way free agency works, a team that signs a player to a contract worth more than $50,000 but less than $65,000 must compensate his former team with a third-round draft choice.

Anything more than $65,000 but less than $75,000 costs a second-round choice. For more than $75,000 but less than $125,00 the former team gets a first-round selection. Between $125,000 and $200,000, the price tag is a first and second-round choice. Anything over $200,000 costs the new club two first-round selections.

This seems a fair system. But there is a way to beat it, or at least the Red skins thought they discovered one last year. They offered Jim Otis a $300,000 contract, but spread it over enough years so the average would be so low that the Cardinals would receive nothing in return.

The Cards yelped for days, to Commissioner Pete Rozelle and anyone who would listen, then suddenly matched the Redskin offer and kept Otis. There has been no evidence of other teams trying similar tactics.

"When you find these people all of a sudden being honest about a system, you know something's wrong," Garvey said. "Because no one is cheating, everyone is covering something up. And that is an agreement to bid for nobody."

Garvey and the players thought they had a fail-safe system when they signed that agreement with the owners. In backup relief, they had Larson, the Minnesota judge who had agreed to look into the matter if the compensation system did not appear to be working.

"Larson gave up jurisdication in July of '77," Garvey said. 'It was a blow to us."

Garvey now frets that his players are no better than the baseball players in the dark ages before Messersmith and McNally, with the owners insisting they have rights that amount to the old baseball reserve clause.

Unlike their baseball brothers, the heavy hitters in the NFL are discovering they do not have much clout.