There was a lot of indulgent laughter from pro football fans when former Oklahoma Coach Bud Wilkinson, 62, emerged from a 15-year hiatus to take his first pro coaching job with the St. Louis Cardinals. After all, the last generation Wilkinson dealt with was the model for today's most popular nostalgia movies: "American Graffiti" and "Grease."

Those who expected compulsory crew cuts and white bucks were immediately disappointed. Wilkinson's training-camp rules are the most relaxed in the NFL. He blunted the torture of two-a-days by scheduling early practice in the cool of the morning with a second workout at dusk when evening breezes were as friendly as ceiling fans. There were no fines for missing a training-table meal at Linwood College in St. Charles, Mo. Conditioning exercises were introduced --very gently after four weeks in camp.

"There are no signs of his having been away for 15 years," confided chubby-cheeked quarterback Jim Hart, now a 13-year veteran. "He's treating us like men, not at all like lower-class citizens.

"He and I have very compatible philosophies of football," Hart insisted, dismissing rumors that he was extremely rankled by the installation of the wishbone T offense that Wilkinson favors. "His philosophy is very similar to that of other coaches in the NFL today. Which is to say, run as much as possible.

"Of course, what dictates how well we do is who runs the ball." Hart said pointedly, underscoring the Cards' need to find a replacement for the classy Terry Metcalf. "We do line up in a full-house backfield with the tight end in the backfield. Then we shift out of that. It's not going to be our sole offense. We only run a few plays off that formation now and, of course, I can drop back and pass from it. Not just short outlet stuff; we are looking for the big play, too.

"We plan to use multiple shifts like Dallas. Today's defenses are so tough and so disguised that a strong running game is the most dependable offense. If I could say I threw only 15 times a game, I'd be the happiest guy in football. When you have to throw so few passes, it means you're in the game all the way."

Another more obvious reason for Hart's happiness is that Bud Wilkinson lets his quarterback call all the plays. Hart hasn't called his own game for five years. Under former coach Don Coryell the plays were called by coaches using hand signals on the sidelines.

"We never used a shuttle system," Hart recalled. "And it was a little complicated keeping one eye on the coach and the other on the field. It took a while to get used to calling plays again, but I'm comfortable with it now. I figure the time we save in not having to signal each other gives us an extra five or 10 plays in a game."

The jury is still out on whether Hart's bonus plays prove productive for the perennially promising (10-4, 1976; 7-7, 1977) but always left-at-the-altar Big Red Machine.

Hart says he is encouraged by Wilkinson's organizational abilities. "Practices are much more structured this year," he observed. In the Coryell years, the scrappy coach would be so close to the action that his nose was bloodied more than once after being caught in the middle of a two-player fist fight.

"Coryell was more of an instructor and a teacher," Hart said. "Coach Wilkinson seems to let assistants do most of the instructing. I'm not saying it's good or bad, but it's what's happening around the league these days."

Hart called his receivers good, which in quarterback parlance means only adequate.

"We need to replace Ike Harris in the worst way; I never understood why he was given up in the first place," groused the quarterback with an often hot, sometimes cold, arm. "And we've lost Metcalf and (Conrad) Dobler. all the football magazines are picking us to end up dead last with four wins and 12 losses.

"But that's fine with me," said Hart, who was barely into college when Wilkinson coached his last football game. "That way we can sneak up on some teams and slap somebody real good."