How good is Larry Kubin and how soon can he help the Redskins?

Answering those questions has become one of the major fascinations of this Redskins training camp. If Kubin is as good as Coach Joe Gibbs believes, he could play a major role in the defense this season.

But if Gibbs is expecting too much too soon from this young linebacker, it could turn into a season of frustration for Kubin and the team.

There is no question Kubin has talent. He is aggressive and durable, a strong tackler with a good linebacker's prime attribute, quick feet. There also is no question he is inexperienced as a middle linebacker, a new position for him. A knee injury two years ago has sharply limited his development.

Not even Gibbs, his biggest fan, can estimate how fast Kubin will improve in camp. He is projected as the Redskins' middle linebacker of the future, but it seems unlikely he has enough time this year to challenge seriously incumbent Neal Olkewicz, the team's steadiest defensive player and second-leading tackler last season.

Yet this defense hardly is proficient enough to keep someone as gifted as Kubin idle for long.

"We've got to make use of his talent," said Larry Peccatiello, the linebacker coach. "We'll give him a legitimate shot at starting in the middle. If he doesn't, then we will create some situations to get him into the game."

Peccatiello acknowledges one of Kubin's attributes is an ability to blitz quarterbacks, a task he performed with gusto at Penn State. If he can't play full-time at middle linebacker and if the Redskins' pass rush continues to struggle, why not use Kubin, a strong 234 pounds, to pressure the quarterback on passing downs?

"That's a definite consideration," Gibbs said. "I see him being used as a third-down pass rusher from his linebacker spot. Other teams do it well, so why can't we? He'll scare some quarterbacks, the way he gets cranked up."

And what better way to become an instant star, at least in the eyes of fans, than to dump a quarterback a few times? Lawrence Taylor proved that last season as a New York Giant rookie.

The Redskins' coaching staff still remembers Kubin's week-long imitation of Taylor before one of the Giants games last year. Kubin was all but unstoppable going after the passer during those workouts.

Kubin's performances in those midweek practices, when he was rehabilitating a serious 1980 knee injury, convinced the Redskins they had gambled correctly by selecting him on the sixth round of the 1981 draft.

Although he could have played one more season at Penn State last year, Kubin chose to sign with Washington. An angry Coach Joe Paterno, unhappy with the pressure put on his player by the Redskins to sign, banned Washington scouts from watching practices or film. It's a difficult restriction, considering the number of prospects produced by Penn State, but Kubin's emergence as a star could make the limitations more palatable.

A year on injured reserve also has better prepared Kubin for this camp. He still is in that no-man's land between rookie and veteran, but at least he is familiar with the defenses and what is expected of him on the field.

"Last year during practices, it was more of a physical thing for me," said Kubin. "Now I've got to remember again that football is mental, too. I'm starting to grasp the duties of a middle linebacker, but I'm still not where I want to be.

"In college, all I really had to do was line up on the outside and go after the quarterback. I never had to worry about pass coverage. Sometimes here, I just want to put down my head and ram someone, but I can't do that. The middle linebacker has too many responsibilities."

Would he mind just playing as a pass-rushing specialist?

"My goal is to be the starting middle linebacker and I'd be lying if I said it wasn't," Kubin said. "I don't want to be known as a role player. I want to be known as a starter. But I also want to play. If blitzing is the way I can do that, I'll be happy to play. I'm trying to be patient and not get frustrated by anything that happens."

The Redskins are trying to remain as patient as possible, not only with Kubin but with such youngsters as Mike Clark, Darryl Grant and Vernon Dean. But unless most of them can provide immediate help this season, the Washington defense will be pressed to show any dramatic--and much needed--improvement.

Kubin is aware of the team's needs, and he has become particularly single-minded about succeeding. "Relentless" is how Peccatiello describes his quest for football knowledge. "If Larry isn't asking questions, he is watching film," Peccatiello said. "He's a smart kid with good motivation. He wants to absorb everything he can.

"What's nice about it is that Larry has the desire to go along with his physical gifts. He is quick, big, strong--all the things you want in your middle linebacker. It appears he can play comfortably at 235 pounds. And he just never gets discouraged. If he makes a mistake, he forgets it and pounds away again. It hasn't taken long in this camp to show us he has great potential."

The Redskins added two veteran offensive linemen to their training camp roster today, tackle Gary Puetz and center Gary Anderson.

Puetz (6-feet-4, 265 pounds) is a nine-year NFL veteran. He last played for New England, but was waived this spring.

Anderson (6-3, 250) was on the Redskins' active roster in 1980. He started at tackle against Oakland and was later released. He will be used at center, where the Redskins have injury problems.

Dean, the Redskins' second-round draft pick, is hobbling after being kicked in the leg during practice, but has continued to work out . . . The Redskins will close practice to the public the middle of next week, just after the veterans start working out . . . The Colts, who will scrimmage the Redskins here Saturday, practiced against the Eagles today. Saturday's session will be closely controlled, with heavy emphasis on passing . . . Receiver Charles Chisley, from the University of District of Columbia, had the most spectacular play of tonight's intrasquad scrimmage, a diving catch of a pass from quarterback Bob Holly. Running back Bobby Batton of Nevada-Las Vegas scored two touchdowns.

The Redskins have become one of the few NFL clubs to hire an assistant weight coach.

Jim Speros, a resident of Potomac, Md., will assist Dan Riley, who was hired after the 1981 season to revamp the Redskins' strength and conditioning program. Speros played football at St. John's High School and Clemson University, where he became assistant weight coach.