NASCAR took a break from psychoanalyzing perennial lightning rod Tony Stewart this week in favor of a new pastime: psychoanalyzing Kurt Busch.

At last week's Nextel All-Star Challenge, Busch attempted to nudge teammate Greg Biffle in a straightaway, initiating a major wreck. Although the two have since mended fences, Biffle sounded off about his teammate after the race, Joe Nemechek said the culprit was "an idiot" and Sterling Marlin went further: "Everybody was being idiots."

Whether the idiocy takes to the track again is a matter for debate in Sunday's Coca-Cola 600, one of the biggest -- and longest -- races on the NASCAR schedule.

Previously, Stewart had been involved in a series of collisions at five races, causing Rusty Wallace and Jamie McMurray to suggest he was driving like "an idiot." Veteran Wallace castigated Stewart in television and radio interviews, and Stewart and Fox analyst Darrell Waltrip exchanged pointed comments through the media.

But amid the verbal sparring and accusations of idiocy, NASCAR veterans acknowledge that a certain degree of aggression and even antagonism in the garage can sustain their sport, even as it continues to move into the mainstream.

"The fans have been going nuts for two weeks," said Wallace, who Friday described his feud with Stewart as over and done. "This fires them up: 'That doggone Stewart, Stewart this, Stewart that.' That'll burn out in about a week, but rivalries create a lot of excitement for NASCAR."

The sport's much-heralded new generation of telegenic stars seems to steer clear of controversy. Jimmie Johnson (Sunday's pole-sitter), Dale Earnhardt Jr. and Matt Kenseth -- all in the top four of the Nextel Cup standings -- traded fuzzy compliments rather than barbs in a joint "SportsCenter" appearance last weekend.

The young stars are so clean-cut that six of them are sponsored by a shaving company. During Sunday's race telecast, Gillette will debut a new commercial starring Earnhardt Jr., Johnson, Kenseth, Ryan Newman, Kevin Harvick and Busch in a "Queer Eye for the Straight Guy" spoof.

But a part of NASCAR's fan base doesn't want to see smiling friends giving each other the thumbs up -- or grooming advice -- as they zoom past.

"What made our sport what it is, is the controversy," said longtime rabble rouser Jimmy Spencer. "I'm just saying that sometimes a war of words is good for the sport. . . . I'll put it this way: No driver wants to see another driver ever get hurt, but believe me, it doesn't make you mad when you see 'em blow up, when you see 'em spin out. . . . You say 'Man, good, son of a [expletive].' I mean, that's the way it is."

Virtually nobody advocates a return to the sport's sometimes brawling past, of which Spencer was an occasional participant. And the recent concerns about Stewart have often centered on safety -- "If someone gets stuck in a fence, someone gets spun out, someone gets hurt, rivalries have gone too far," Wallace said this week.

Still, when polarizing figures emerge, drivers say, the fans respond.

"It's a heck of a lot to fun to pull for somebody, to feel like you know 'em, to feel like when they're doing well you're doing well," said Jeff Burton, one of Stewart's critics this season. "The other thing is, it's just as much fun to pull against somebody. . . . . Having a villain or a guy that you love to hate is important for the sport."

Lately, the No. 1 villain has been Stewart, who was roundly booed before the last points race in Richmond.

Earlier in his career, he struggled with anger issues off the track, earning rebukes and probation from NASCAR after several confrontations with journalists. This season, the controversy has come on the track, with Wallace and Waltrip leading a chorus claiming that Stewart was out of control, and NASCAR officials meeting with him before the May 2 race in California.

After weeks in the spotlight, Stewart declined to be interviewed about those incidents in this week's run-up to the Coca-Cola 600.

The 2002 Cup champion, currently fifth in the points race, has privately apologized at least twice this season: after nearly wrecking Terry Labonte during the cool-down lap at Talladega, and after getting into Jeff Gordon at California Speedway, a problem Stewart later blamed on a faulty spotter.

J.D. Gibbs, president of Joe Gibbs Racing, which owns Stewart's car, said several of the recent incidents were "just racing." But Gibbs acknowledged that "fewer issues would be a good thing." Burgeoning corporate sponsorship places demands on driver decorum that didn't exist 25 years ago, Gibbs said, and a growing media contingent ensures that sound bites live on for days.

But Gibbs, too, said that the tete-a-tetes are popular with fans, although he added that "like reality shows, they're fun to watch, when it's not you."

"That's what makes the sport interesting," Gibbs added. "If no one really cares, if no one got upset, what would that tell you about the drivers and their passion?"

And Stewart's fans say they have no complaints.

"I don't think there's a driver here as aggressive as Tony on the track; personally, that's what I like most about him," said Stewart backer Ken Burns, 49.

Race observers say NASCAR will continue to seek a balance between aggression and civility.

"If everybody shot off we'd be taken back to some dirt tracks we used to race in -- race a while and fight a while -- and nobody would put up with it," said longtime owner Robert Yates, who has been around the sport for more than 30 years. "But you're going to have a personality that pops out here a little more than the other guys. If we didn't have that, it would be a boring place."

Ryan Newman gestures toward mercurial Tony Stewart (20). "If everybody shot off we'd be taken back to some dirt tracks . . . and nobody would put up with it," said longtime owner Robert Yates.Tony Stewart, 2002 Cup champion, is one of the sport's most polarizing figures on, off the track.