The pitch was direct and to the point spread: "Trust a service that trusts itself . . . please consider us before you go to sea without a lifeboat."

Except, in this particular ad, the particular tout-service proceeded to try to build its credibility by knocking the integrity of other professional tipsters.

No creature or computer exists that can pick 70 percent-plus against the point spread over any extended period of time. Many services just plain lie about past record," the ad began, adding: "They claim fabulous successes for years they weren't even in the business. Others release games in so many different categories that something is bound to come through . . ."

Oh, yeah. I know one character who releases four different sets of games each weekend plus "Monday night specials" and "Friday phone features." At least one of those six categories figures to show a profit. That's the one he publicizes.

Then there's the service that gives you back your money plus a little extra for each loser released. If you pay $100 for each game and one wins and two lose, they may refund $220 ( $110 for each loser) of the $300 paid -- but they're still $80 up. How sweet it is.

And how about the "lock" games, guaranteed outcomes that "can't miss?" As this particular ad pointed out: "They are amiss. For example, two years ago after a regular-season 'lock' win, one service hyped to death a 'bowl lock of the decade.' This 'bowl lock' lost miserable."

This does not mean that all tout services are, to put it kindly, untrustworthy. There are a few good ones. But they are few and far between geographically and none of them have fared as well over the last year and a quarter as "the (under) dog at home."

I continue to believe there has to be more to covering the spread than taking the points and the home field, although recent statistics would indicate this is the easy approach for the armchair traveler. Two out of every three dogs-at-home continue to play better than they're rated.

So I'll tempt the trend again this week by taking San Diego giving 1 point at Denver and Miami giving 2 Points Monday night at Oakland. Each is worth an imaginary $250.

Washington also attracts $250, getting 4 points at Philadelphia, as does Buffalo giving 6 at home to Chicago. That clears the decks for three more selections: Dallas ($500) giving 7 1/2 at Minnesota, Tampa Bay ( $500) giving 4 1/2 at the New York Giants and New England ($1,000) giving 13 at home against Detroit.

San Diego has much better balance that Denver, which desperately needs a quarterback. The Bronco defense is not playing up to its 1977-78 form, either.

Miami will apply more pressure to Ken Stabler than Oakland will to Bob Griese, and the Dolphins have by far the better ground game.

Buffalo has always beaten the spread at home since Chuck Knox took over, while the Redskins are peaking right now, just as they did last season. I want to bute my (or his) tongue, but I have to admit that Joe Theismann is showing remarkable restraint for the Skins.

The spot of 4 1/2 with Tampa Bay seems small. What are the Giants going to use for offense? Simms? You have to be kidding. Dallas has its offense in gear. Only a repeat of its mistakes at Cleveland can keep it from rolling over the Vikings.

Finally, there's Detroit at New England. This game doesn't have a number in my book. The Lions will not be able to score more than 10 points. The Patriots will hit for 30 or more unless Grogan is worse than usual.

In other games this week, Las Vegas lists Pittsburgh 4 at Cleveland, Atlanta 6 1/2 over Green Bay, Kansas City at Cincinnati even, Houston 7 1/2 over St. Louis, Los Angeles 4 at New Orleans, the New York Jets 2 1/2 at Baltimore and Seattle 5 at San Francisco.