Kurt Busch often has people talking, but he never has them laughing. He can be amazing but not amusing. Even trying to relax, he can bring a sense of tension into a room.
At the spikes in his anger and the depths of his humility, his voice tends to quaver so that sometimes you can't hear the difference in his moods.
Enter Brad Keselowski, opposite Busch in the latest feud to flare in NASCAR, at Martinsville last Sunday. He too has people talking often, but he keeps them laughing all the way. He can relax a room just by walking in the door. He is never awkward.
After they collided in the pits at Martinsville and blamed each other, it was as if the two ancient masks that symbolize theater, one laughing and the other crying, were facing nose to nose.
Is this to be continued Sunday at Texas? Unlikely. Sanity usually trumps ire where speeds approach 200 mph entering corners.
But this isn't over. These are the two drivers least likely to let go of such conflict, and two of the most steeped in the old NASCAR code of payback. So we shall see it again. The questions are when, where and whether it will continue beyond next time.
They are just too opposite for this matter to be fleeting.
Since Busch's arrival in Cup in 2001, his path could be plotted on a graph like the ups and downs of the Dow Jones average. His line has undulated from spectacular to exasperating to pitiable, and up again and down again.
Right now there is an uptick -- with foreboding.
Busch's win at Martinsville broke an 83-race losing streak that was largely due to his well-documented spells of being brattish. He wore out the patience of half a Cup garage full of team owners. First Jack Roush gave up, then the patient Roger Penske and then the ultra-patient James Finch, before Busch hit a career-low and began to claw his way back up last year with the bootstraps Furniture Row team.
And then in a surprise, largely apart from co-owner Tony Stewart, Gene Haas took a leap of faith on pure talent -- nobody questions that in Kurt -- and signed Busch for this year.
Surely you know the supposedly Chinese (but actually English) ironic blessing, "May you live in interesting times."
In a NASCAR garage, that might translate to, "May you hire Kurt Busch." Or, in the grandstands or infield, "May you be a Kurt Busch fan."
The certainty, if you choose to ride with Kurt, is turbulence.
Keselowski has rarely, if ever, done anything but delight his car owners, first Dale Earnhardt Jr. in Nationwide, then Finch, who sent him to his first Cup win, then Penske, who sent him to his first Nationwide title in 2010 and first Cup title in 2012.
Even at Keselowski's most rollicking public moment, his tipsy appearance on "SportsCenter" after swilling sponsor Miller Lite's product the night he won the Cup, the dignified Penske appeared amused.
Even when he's angry, Keselowski is cool, in charge. Thus his words, as he looked into a live TV camera Sunday while his car was being patched up in the garage: "Thanks, Kurt. Appreciate it, bud."
Thus he summarized a couple of points that appear valid, upon further review of video of the incident, including several replays in slow motion.
Trying to exit his pit, Keselowski was cut off by Kasey Kahne. Then he tried to steer clear. Then Busch, coming by -- coming through! -- appeared to give Keslowski less room than he could have.
Busch appeared to instigate an instantaneous game of chicken.
"Kurt just accelerated and drove through us -- absolutely drove through us," Keselowski said, firmly but coolly. "I tell you, I'm about tired of his recklessness."
Keselowski has another point there. Busch's style is on the ragged edge between the spectacular and the reckless, driven by selfishness.
This time, rather than give just a couple of feet, as most other drivers would, especially early in a race at tight, little Martinsville, Busch appeared to dare Keselowski to pull out -- but Keselowski had no other place to go.
This sort of thing seems almost reflexive with Busch. Call it reflexive recklessness. Or reckless reflexes. (That's exactly what he'll have to curb, lest he get himself in trouble when he tries to run the Indianapolis 500 in the first half of his "double" in May.)
But now hear Busch, feeling victimized as usual, on his radio after the incident, as relayed by Fox to its audience.
"We just got destroyed by the 2 car coming out of the pits," Busch said. "The left rear just got hammered."
And now the quavering voice: "We're probably ruined for the rest of the day."
Giving up prematurely, at least verbally, is a tendency he shares with his younger brother, Kyle. They tend to say it's over before it's over. Maybe it's generational; in the absence of instant gratification, there's instant disappointment.
With Kurt on Sunday, it clearly was nowhere near over. He went on to win.
Keselowski, with the front bodywork stripped from his car, returned to the track and waited on Kurt, then engaged him door to door. Keselowski continued to rough up Busch for about 16 laps.
Keselowski's methods were entirely acceptable by NASCAR tradition.
"Brad didn't wreck him; he just sent him a little message," Fox analyst Darrell Waltrip, who from his own driving days knew exactly what he was seeing, said on the air. "Brad is doing exactly what some of us older guys would do -- we would haunt you. Every time you saw me, you knew I was going to be in your way. Every time you saw me, you knew I might shove you up the track a little bit."
In Waltrip's generation, that sort of thing might continue from race to race, and is likely to in this case.
It's what Keselowski did, not what he said, that likely will haunt Busch for weeks to come.
In the winner's interview, Busch told reporters at the track that "I steered right to go around Brad."
Evidence of that is hard to find on the video. It appeared Busch kept a straight line.
Then, "Once we were back out running," Busch said, "he targeted us; he was aiming for us."
Obviously, absolutely true.
"He tried to flatten all four of my tires," Busch said. But there was no evidence of that on the video. Now Busch's bitterness surfaced: "That's a punk-a-- move."
And finally, "He will get what he gets back when I decide to give it back."
That's ominous. Even in victory, storm clouds were gathering on Kurt Busch's horizon. Even in this uptick, there was foreboding of a downturn, back into turbulence.