With Dallas and the Redskins on the mind today, these topics: How can they do that to Joe Theismann? How can they leave him out of the Pro Bowl when he ought to be in? . . . And we'll meet Alice Musselman, a Redskin fan who saw the very first game in Washington in 1937 and says, "I would not go away from the TV Sunday for anything." . . . And we will explain, from the safety of an undeground vault, why the Cowboys will win Sunday, 24-17.

First, Theismann . . .

Roger Staubach of Dallas and Archie Manning of New Orleans were picked as the National Conference quarterbacks for the Pro Bowl, leaving out Theismann.

The NFL players and coaches who did the voting made a mistake.

Staubach, no one can argue.

His statistics are the best in the whole league. Tony Dorsett can get hurt. Drew Pearson can hot dog it unitl his leg falls off. The Cowboys will win without them. Let Roger Staubach get hurt, and the Cowboys become plowboys.

But Archie Manning? Everyone can argue Archie Manning.

Not that he's bad. He's wonderful. In his seventh season as a starter, Manning was the most valuable player the Saints had, just as Staubach and Theismann were the MVPs on their teams.

But Theismann had a much better year than Manning. There are numbers. According to the NFL's complex quarterback ratings, Staubach was No. 1 in his conference. Theismann No. 2 and then Manning. And it wasn't close.

The NFL ratings are mysterious, of course. They are based on a formula involving percentage of touchdown passes, percentage of interceptions. average gain per pass and heaven knows what else. Pete Rozelle says to trust him.

Anyway, Staubach had a 91.8 rating, more than seven points ahead of the next best man in the NFL, San Diego's Dan Fouts (84.4).

Theismann was No. 3 in the NFL with an 83.1 rating.

Manning, while third in his conference, was only eighth overall at 77.0.

Theismann threw more touchdown passes than Manning (19 to 14), suffered fewer interceptions (13 to 17) and, inconsequentially, was behind Manning on completion percentage 59.4 to 59.8).

Theismann undoubtedly was hurt in the voting by his sudden emergence as a star this season. Manning, a Pro Bowl starter and hero last year, was fresh in the voter's minds.

"I can't see that, either," said Alice Musselman, who once loved Sonny Jurgensen's work at quarterback and now believes Joe Theismann to be swell. "Theismann ought to be in that Pro Bowl game. He and John Riggins, oh, my goodness, I don't know what the Redskins would have done without them.

Friends of Mrs. Musselman say the sweet lady was a teen-ager when Teddy Roosevelt put a stuffed bear in the White House. What Mrs. Musselman says is, "I wouldn't dare tell you how old I am. My age? My age is just a number. I've been celebratng my 39th birthday every year. It's a nice number. Jack Benny liked it and so do I."

Alice Musselman, 39, saw the Redskins play in Washington 42 years ago.

"I saw them play the Galloping Ghost," she said.

Red Grange, the Galloping Ghost of Illinois fame, played for the Chicago Bears back then.

"We paid $1 to get in," Mrs. Musselman said. "The next year, it cost us $3.50."

In 1937, the Redskins won the league championship, giving George Preston Marshall incentive to see what the traffic would bear in 1938.Homer Musselman, Alice's husband ponied up the money for season tickets until he died in 1956.

If Mrs. Musselman doesn't go to the games anymore, it doesn't mean she doesn't care.

"Oh, the Redskins are my life," she said. "I watch them on the TV all the time. I would not miss a game. I watch them like nobody's business. And I tell them what to do."

And what would she tell the Redskins to do with the Cowboys this Sunday?

"Watch Dorsett," Mrs. Musselman said. "Get him. Stop him. Sic somebody on him."

Who will win?

"We have beaten them before and the Cowboys have people hurt," she said. "If the Redskins play the way they have the last two games, we'll win."

The Cowboys will win.

They will win because their defensive line will play an outstanding game. Without Randy White, who was hurt, and with John Dutton still ineffective, the Cowboy defensive line was beaten badly in the Redskin's 34-20 victory here a month ago. That won't happen again.

White is, if not healthy, at least working on 1-1/2 good feet, which makes him as good as any other two linemen in the world. And Dutton, if not Too Tall Jones, is now good enough to be in the starting lineup.

With an improved pass rush, the Cowboys will not give Theismann all that time he had to pick apart the Dallas quarterbacks the first time.

Tony Dorsett, with a bad shoulder, says he is going to play Sunday. So does Drew Pearson; who twisted his kneee celebrating a touchdown catch two weeks ago.It doesn't make much difference if they play or not. The Cowboys offense needs only Staubach working well, and even folks who have been around as long as Mrs. Musselman can't remember Staubach playing poorly in an important game.

The Cowboys were at their worst in that 34-20 loss to Washington here a month ago. The Redskins may have been at their best. Both situations will change Sunday when they go to Texas Stadium in front of 70,000 Texans. Dallas 24, Washington 17.