Tom Pelissero

USA TODAY Sports

SANTA CLARA, Calif. – Jim Harbaugh had lines in that Dockers ad starring his wife that made the Internet rounds a couple months back, but they ended up on the cutting-room floor.

"I'm sure they know what they're doing," the San Francisco 49ers' coach told USA TODAY Sports, sitting in his cluttered, unassuming office before a recent practice.

"Because especially the players here and most people that I talk to say they loved it, what a great job my wife (Sarah) did in the commercial, and then the second thing they loved was that I didn't have any lines. 'And the best part was you didn't say anything!'"

It played off the version of Harbaugh that spawns Internet memes: perpetually dressed in the same black sweatshirt and shapeless khaki pants, too immersed in football to care about his appearance, a little too weird to do more in a TV commercial than grin and nod.

"I enjoyed my wife doing it," Harbaugh said. "People will from time to time say, 'Why him?'"

That Harbaugh is one of the NFL's smartest and most successful head coaches as he enters his fourth season with the 49ers can get lost in the clothes, and the sideline histrionics, and the alternate two-word answers and elaborate metaphors he uses with the media.

If anything, though, Harbaugh seems to embrace the caricature.

"Uh, caricature?"

Or maybe that's just the real him.

"Uh-huh. Yeah. It could be," Harbaugh said. "They combine, honestly."

Harbaugh turned 50 in December. When he sees himself on TV these days, he sees his father.

"I just look like him. I sound like him," Harbaugh said. "I remember him when he was at that age. I'm pretty darn happy about that."

When Jack Harbaugh was 50, it was 1989 and he was beginning a 14-year stint as head coach at Western Kentucky. He left after the Hilltoppers won the Division I-AA national title in 2002.

Jim Harbaugh says he sees himself as the 49ers' coach "a long time." But talks about extending his contract – which runs through 2015 – are on hold until after a season Harbaugh surely hopes will bring his own title and all the leverage that comes with it.

The 49ers remain one of the most talented and complete teams in the NFL. Harbaugh says this is also "the least unhappy team I've ever been around," which is about as close as he'll come to praising his players' psyche before they play a game.

"That's not a word that I would put with the two: football and happy," Harbaugh said. "It's a hard, rough, tough sport. Not a lot of fun. I mean, it's fun when you win …"

And for whatever disagreement exists over the money and power Harbaugh deserves, that's what he does: win. As a coach, he always has won, dating to a 29-6 run at the University of San Diego from 2004 to 2006 and his turnaround of a moribund Stanford program to a 12-1 season in 2010.

The 49ers have won so much the past three years – a 41-14-1 record (including playoffs), three straight NFC championship game appearances, a Super Bowl trip – it's easy to forget the eight-year playoff drought that preceded Harbaugh's arrival.

"He's made for this job," tight end Vernon Davis said. "A lot of coaches, they coach the game of football. But he's made for this. That's what sets him apart."

There weren't wholesale personnel changes when Harbaugh took over in 2011. The explanation for the run of success since is, in the words of running back Frank Gore: "Bringing the right coaches in that know what they're doing."

There are few staffs better than the one put together by Harbaugh, whom Gore says "lets everybody get a piece of the puzzle." But it's Harbaugh who walks every offensive play into the huddle during practice. It's Harbaugh who sets the tone in the meeting rooms.

"He's a magnificent coach," Davis said. "He's good at what he do. The players, they just gravitate. They lean on him for everything – advice and energy. You can fill a stadium with the amount of energy that he has."

It's probably hyperbole when Harbaugh says he "didn't have one bad day last year. Not one tired day, not one down day the entire year." Everyone has gripes about their job. If Harbaugh is coaching elsewhere in two years – he'd have plenty of options – there will be reasons why.

But when it comes to the idea Harbaugh's hard-charging style will burn out himself or those around him here, he says he doesn't buy it. He still has the energy to spend part of his offseason building houses in Peru. He says he still has the desire to show up to work and – in words he often repeats to his players – attack each day with an enthusiasm unknown to mankind.

And Harbaugh seems uniquely comfortable in his own skin, not to mention his own clothes, which still don't change much now that the grind of what could be a pivotal season for his future is under way.

"There's times my 5-year-old daughter, Adie, and Katie, the 3-year-old, and Jack, who's almost 2 – they literally will be grabbing my pants. 'Don't go daddy. Come home. Come back from work. Don't go to work,'" Harbaugh said.

"That'll be the thing that someday makes me not coach anymore. But the flip side of that is I know that it's an example that's being set for them – that their dad is doing what he loves and the example of working very hard at it is a really good example for them.

"There's a struggle to it. It's a lot of practice. I get a big thrill out of football, don't get me wrong. Stepping on the practice field, the games (is an) unbelievable thrill, and then winning is really fun. But it's a struggle. Football players come to enjoy the struggle."