Dave’s Six-Month Checkup : Why did David Letterman become a nicer guy? Why then doesn’t he lay off NBC? Is he glad the ratings are great? : Where the heck is Jay Leno in all this? Is Dave really happy? Do you really have to ask? Well, we were just curious

“We all went into this with more than a little sense of dread,” says David Letterman, sizing up his late-night CBS show, which has become the talk of television. “I was worried about being embarrassed.”

But half a year now has passed since CBS’ “Late Show With David Letterman” debuted, and it has taken off like a rocket in its head-to-head competition with “The Tonight Show”--where NBC had rejected him as the heir to Johnny Carson, giving the plum job to Jay Leno instead.

In that half year, Letterman has turned late-night TV around, doing what no other performer has ever done--stripping NBC of the “Tonight Show” dominance that it had established for nearly four decades under Steve Allen, Jack Paar and Carson.

Leno, as NBC repeatedly points out, is doing well himself--and steadily improving--in the ratings competition. But in that case, the Letterman series is a phenomenon. As of audience measurements through Feb. 6, it had defeated “Tonight” for 23 consecutive weeks in the ratings.

If the pattern continues, NBC, which believed that Letterman had a cultish and essentially limited audience appeal--fine for 12:35 a.m. but not mainstream enough for 11:35 p.m.--will be stuck with the reputation of committing one of the major blunders in television history by allowing the comedian to get away.

NBC Entertainment executives declined to compare the two shows or their stars at this point. What they are hoping for, of course, is a late-night replay of the tortoise and the hare, in which Leno would weather the storm and eventually reclaim the top spot, vindicating NBC’s judgment. What is certain, however, is that regardless of the eventual statistical outcome, Letterman has given late-night TV and CBS a huge shot in the arm--and much sooner than even his most ardent supporters thought possible.

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Letterman and his co-executive producers, Peter Lassally and Robert Morton, concur that they are all surprised at the quick payoff--especially since their “Late Show” started with only two-thirds of CBS stations carrying it in its regular time slot against the 100% affiliate clearance of “The Tonight Show.”

But Letterman the showman clearly had given his new gig and his image at 11:35 p.m. some serious thought.

“I think David did a remarkable job in reinventing himself,” says Lassally, who formerly worked on “The Tonight Show” with Carson. “I know the obvious things to see are that he wears suits and nice clothes. But his whole attitude is completely different. He’s warmer and friendlier and has more energy than ever before. He used to have the tag on him of being mean-spirited, and that tag has been destroyed.”

How intentional was that?

“I think it was very intentional,” says Lassally.

“Peter is exactly right,” Letterman says of the changes. “And the only thing I can liken it to is, you meet a girl and you fall in love with her and now it’s time to meet her parents and you want to make absolutely sure you make the best impression possible on these people.

“I think that was the kind of pressure I felt going from 12:30 to 11:30--new people you want to make an impression on. I know what my limitations are. I know the kind of mistakes I can make. And I just wanted to make absolutely certain that I could sidestep them.”

Does that mean he decided to ease up on the show’s edginess, a trademark of his 11-year NBC series? Has he gotten feedback from people who think he has become too nice a guy on CBS?

“No, I’ve not heard that. I would guess that maybe people feel that. I don’t think there has been a marked change, but I was bound and determined to get rid of the idea that I was mean to my guests. I believe that was something that was established early in the old show and just became part of the myth.”

It is, of course, not myth to say that Letterman’s appeal is based partly on his instincts for the jugular.

“I’m not saying I wasn’t ever mean to guests,” he says, adding that the reputation “was difficult for us to get out from under. That was the one goal I set for myself. I said, ‘I just don’t want this anymore,’ because in my mind I was never being mean to guests. Yes, I could understand how it could be perceived that way, and of course perception is reality. So that was probably one thing that I would have at the top of my list: OK, whatever you have to do, don’t let people have the reaction that you’re being mean to somebody.”

For Morton, other factors came into play in the move to CBS: “To do well with only 65% live clearance (now up to 80%) is almost shocking--like having one arm tied behind your back--but just getting the job has been such a kick in the pants for the staff. It’s driven David to a quality level that’s awesome. At NBC the last few years, we felt like bastard kids--’Let them do their little show at 12:30.’

“When we premiered (on CBS last Aug. 30), David saw the crown was up for grabs and went for it. NBC didn’t realize that David Letterman was a franchise player. I think Jay Leno is very good but not a franchise. NBC did not think David could play at 11:30, and they misjudged it.”

NBC’s notion that Letterman--an influential and money-making performer--might have remained on the network at 12:35 a.m., in effect playing second fiddle to Leno, is hard to fathom. No way, says Letterman.

“What’s even sillier,” he says, “toward the end of my time at NBC, they came up with a plan whereby I would stay at NBC at 12:30, and then in May of ‘94, I would take over ‘The Tonight Show.’

“And I considered it for a while. And occasionally we laugh about it because if I had done that, Conan O’Brien (Letterman’s replacement on NBC) would still be a writer, I would still be doing 12:30 and we would still be waiting to do our show in May. And that’s just completely ludicrous now. I can’t even imagine why I would consider that for half a second.

“I did feel that when Jay got ‘The Tonight Show,’ for me that was really when my relationship with the network ended because I felt emotionally and in a real visceral sense that this doesn’t make any sense--that you have Jay Leno and then you have me. What’s the point? You’re duplicating programming. I think Jay Leno and Conan O’Brien make perfect sense. But not me.”

Yet Letterman acknowledges that he considered the eleventh-hour NBC offer because he had wanted to succeed Carson on “The Tonight Show” for so long.

“Oh, sure. Yeah. It was something that I took very seriously. I remember the day we were talking to Michael Ovitz (his agent), and he said, ‘You have two offers. One is NBC: Take over “The Tonight Show” in May of 1994. Or you go in the next three months, six months, to CBS and start your own show.’ Michael Ovitz said, ‘We strongly suggest that you take the CBS offer.’

“I think we were all hoping there was a slight chance we could go to Burbank and start doing ‘The Tonight Show.’ But Peter (Lassally), who had been working long and hard to get ‘The Tonight Show’ after it had been given to Jay, and Morty (Morton) said, ‘No, you can’t take “The Tonight Show” under these circumstances.’ So I wrestled with it for two or three days, and then I finally realized you have to take this chance.

“I mean, too much had happened. It would have been so unpleasant. It would have appeared that Jay would have been ousted from his job. And you know, he wanted that job as much or more than I did. If we had taken that deal, it would have been very unpleasant, very messy.

“I absolutely wanted ‘The Tonight Show.’ But I realized that I didn’t get what I wanted, so I have to make the best of what I have. And it wasn’t until maybe a week or two into (the new CBS show) that I realized that what I had maybe was the best thing after all for me. So it kind of dawned on me gradually.”

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What became clear during the protracted negotiations between NBC and Letterman from 1991 to 1993 was that the genial, Hollywood-based Leno had won the ear of management, particularly in Burbank.

Letterman, New York-based, speaks warmly of his relationships with former NBC honchos Grant Tinker and Brandon Tartikoff: “These guys put me in business.” But particularly after General Electric bought NBC in the mid-1980s, with Tinker gone and Tartikoff to follow later, it seemed that Letterman’s relationships with management were not the same, and the stinging barbs he aimed at the network and GE were a little too realistic to be just fun and games.

Yet here he was wanting “The Tonight Show” badly--although he was tactfully restrained about it in public statements--and at the same time he and the management that would decide his future appeared to be drifting apart publicly. How does he assess his difficult associations with the network’s management during that critical period?

“I will take the responsibility for all of that,” he says. “I think that we felt for a long, long time like we were laboring in kind of anonymity. And I allowed myself to generate some resentments--most of them petty, by the way. And I think it was an area we just weren’t actively nurturing.

“I think I would have to take responsibility for the deterioration of the relationship. At times we’d go years without trouble. The kind of thing that sort of upset me--and I guess I overreacted to it--was when they wanted to rent out our studio during the day to Maury Povich (in 1991).

“I just thought: No, this isn’t right. And it’s not right because I’m Dave Letterman--it’s not right because that’s not how you run a TV show. You don’t slam another production in there and inconvenience everybody--because TV, night in and night out, is a dogfight and you need every little advantage you can muster.

“So I felt like, ‘This is an ideological disagreement. These people don’t understand that it’s not ego. It’s not because I think I’m Mr. Big Shot. It’s because it doesn’t make any sense. It’s a mistake.’ And I believe that’s when I sort of gradually got the feeling like my time there was limited, that I was ultimately expendable.”

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Letterman is definitely not expendable at CBS. In fact, his hourlong show gets prominent mention in the network’s latest, upbeat earnings report, which shows a 39% increase in net income for the fourth quarter of 1993 compared to the previous year. Example: “The CBS Television Network is now heading toward an exceptional triple crown--winning the ratings races in prime time, daytime and late-night television in the current season.”

And this: “(CBS) Television Network revenue growth was aided by higher pricing during the prime evening hours and by the debut of ‘Late Show With David Letterman.’ ”

Rumors persist that CBS may merge with a studio--perhaps Disney--in the not-too-distant future and, if so, the Letterman show can only make the network more valuable.

Ironically, the success of his show is also a healthy boost for all of network TV because there now are three successful late-night series to shore up one of the few remaining strong areas of the Big Three broadcasters--CBS, NBC and ABC. CBS has Letterman, NBC has Leno and ABC has Ted Koppel’s “Nightline.”

Letterman says he’s surprised by the strength of the 11:30 competition: “Before we went on the air, I assumed that for us to succeed, we absolutely had to take away audience from ‘The Tonight Show’ and, moreover, pretty much put them out of business.

“I felt that you have ‘Nightline,’ you have ‘The Tonight Show’ and that’s the limit of the audience. And while I think we have had an effect on the ratings of ‘The Tonight Show,’ it seems like we have generated or developed or brought in a brand-new group of people who are not directly affected by ‘The Tonight Show’ night in and night out.

“In the beginning, it was also frightening because I thought that these people are tourists, they’re not looking to buy into the neighborhood, they’re just passing through. But so far we’ve been incredibly lucky.”

As for Letterman’s value to top-ranked CBS--where his ratings success is already paying off on his three-year, $42-million deal--”his impact as a revenue generator is only going to grow in future negotiations (with sponsors),” says David Poltrack, the network’s senior vice president of planning and research.

“His impact on our fourth-quarter earnings was reflected at a modest guaranteed rating. We sold this show at a 4.1 rating and it’s getting a 5.6 (each point represents 942,000 homes). In the next negotiation, we’ll be selling it at a 5.6. There’s always a one-season lag because you’re always selling off speculation, which in this case was conservative. We didn’t want to promise more than we could deliver.”

Through their first 23 weeks of competition, Letterman, with his 5.6 ratings average, drew 18% of the available viewers. Leno, meanwhile, had a 4.4 rating and a 13% share. A year ago, says Poltrack, CBS, then showing action series in the time slot now occupied by Letterman, was averaging a 3.0 rating and 10 share.

“We’re up 87%, Leno is down 6% from a year ago,” says Poltrack, adding that “Nightline” is “essentially unchanged.” The CBS researcher says that, in replacing the old action series, Letterman has also lifted the network’s tune-in by 118% with 18-to-49-year-old viewers and 144% with the 25-to-54-year-old audience--the categories most advertisers lust over.

The importance of CBS stations carrying the show in its regular network time slot--rather than on a delayed basis--was underscored by Poltrack. Citing key cities such as Washington, Dallas and Kansas City where ratings jumped significantly when they recently began carrying the series in its regular time period, he says:

“Affiliates are getting out of contracts and moving him into a live situation. We anticipate this will continue until he has virtually complete live clearance and that his advantage will thus grow. The track record of those stations that have converted is forming the major selling point to get the others to switch.”

NBC Research counters that while he is behind, Leno has steadily “trended up” from his ratings six months ago in total homes, audience share and the key young-adult demographics. For example, in his first 12 weeks against Letterman, he averaged a 4 rating, but in the next 11 weeks he rose to a 4.6--a 15% increase.

For Letterman, being the solid leader at the moment is a bit mind-boggling: “With the disadvantage of the affiliate clearances . . . I thought if we could have been at least within striking distance of ‘Nightline’ or ‘The Tonight Show,’ then we could have thought, ‘OK, we’re trying, we’re building.’ But when we saw the ratings for the first night, a huge weight had been lifted.”

Now it is down to the nitty-gritty. Letterman and Leno are doing well against each other in their home-base cities. So during the May ratings sweeps, they’ll invade each other’s territory for a week each--Leno going to New York and Letterman coming to Los Angeles--in hopes of gaining more viewers in a couple of their important weak spots, which happen to be the nation’s two top TV markets.

Los Angeles has not exactly gone overboard for Letterman despite his success elsewhere. CBS sources think it’s partly because the network’s local station, KCBS-TV, “is a weak performer,” including its critical 11 p.m. news that is Letterman’s lead-in. Poltrack thinks “community loyalty” for the hometown Leno show is another factor. Lassally agrees.

“We’re also coming (to Los Angeles),” says Letterman, “because we’ve established ourselves, we’re doing very well and we want to come right into the heart of American television, which is obviously Los Angeles.”

*

One day, after Leno had gotten the “Tonight Show” job, Letterman picked up a publication in New York and saw an advertisement touting the new heir to the late-night series, the man who would follow in the footsteps of Allen, Paar and Carson.

“It broke my heart,” Letterman says. “I thought it would have been a real pat on the back, a real accomplishment, to have been in that picture.”

Carson is a close personal friend, and Letterman’s director, Hal Gurnee--who has inventively incorporated the New York setting into the show--once worked for Paar. There is little doubt that Letterman felt he was a natural part of “The Tonight Show” legacy.

He sought advice from some of those connected with the legacy, including Carson and Lassally, before finally saying goodby to NBC and accepting CBS’ offer. In addition, says Letterman, he talked to Morton, Gurnee and Jude Brennan, one of his producers.

“What Carson has done for me and means to me represents a great influence,” Letterman says. “So after talking to all of those people--and the opinions ranged from ‘You’re nuts if you stay’ to ‘You gotta get out’--and then after I talked to Carson, I felt like I had now talked to the people who are the most important folks in my life. And I don’t believe they would mislead me.”

When Letterman left, it was yet a further breakup of a great, three-program, late-night NBC dynasty. At its height, it included Carson, Letterman and Bob Costas, who is also ending his wee-hours show on the network at the end of this week, although he is remaining at NBC. The new late-night NBC lineup is Leno, O’Brien and, beginning Feb. 28, Greg Kinnear, who has a program on the E! cable network.

Letterman, meanwhile, finally seems at peace with his decision. Beyond the ratings and the money, a sense of freedom permeates his enthusiasm: “We’ve been sort of giddy ever since we went on the air. We just couldn’t believe that all of a sudden, people were looking at this little nickel-and-dime thing that we’ve been doing for years and were, by and large, pleased with it. It’s the most rewarding thing I’ve ever encountered in my life.

“It’s like the underdog team that gets into the World Series and takes the first three games, and you think, ‘Man, we’ve got a shot at this thing,’ and then the rest of the Series they’re playing over their head.”

On Mom:

“CBS . . . said, ‘You can do anything you want with the Olympics. You can send a crew over there, you can go there.’ They gave us pretty much a blank check. We didn’t know what to do. And then my mother’s name came up. I think we were sort of out of ideas. When you’re out of ideas, you go to your mom.’

On middle age:

“No one is more aware on a minute-by-minute basis that I will be 50 in four years. I have a quiet little goal . . . which is: Let’s take a look at this when you’re 50 and see if the thing is still viable. I don’t believe we are the avant-garde. I wish I could say we’re leading the way and know exactly what we’re doing. The truth of it is we’re hanging on, we’re chasing a truck, we’re doing the best we can.’

Dave, Jay and Arsenio have declared a truce in the late-night booking wars. Page 72.