SANTA CLARA – Focused and loose at the same time. That's a good one. Even when Jim Harbaugh tosses out one- liners or erupts into brief, halting laughter, his features tighten up faster than the spirals he used to throw.

But, hey, he's the coach, and the 49ers are back in the playoffs, and he has done amazing things during his rookie NFL coaching season. He can sip his diet sodas by the caseloads – and he does – and everyone else around here swallows whatever he serves and whatever he says.

"No one expected us to be here," tight end Vernon Davis reminded, "and coach Harbaugh is a big reason for that."

Say that again.

No one expected the 49ers to be here. This was supposed to be Harbaugh's honeymoon season, a year to evaluate the roster and coax decent performances out of Alex Smith while grooming rookie quarterback Colin Kaepernick.

Well, so much for offseason detail work, game planning and prognostication.

Harbaugh, 48, has the 49ers in the playoffs for the first time since the eminently huggable Steve Mariucci guided his team to the NFC West championship in 2002. What is that now? A decade ago?

While Harbaugh is hardly of the teddy bearish, Mariucci variety, he did what Dennis Erickson, Mike Nolan and Mike Singletary (2003-10) failed to do: win more often than lose.

None of this would have happened, of course, if Harbaugh hadn't been able to rehabilitate Smith, the physically and emotionally bruised veteran who simply refused to go away. Smith wanted one more season, one more chance, one more coach. He wanted whatever Harbaugh was pitching.

"He's authentic," Smith said. "He's an honest coach, and he coaches everybody the same way, no matter who you are."

This Smith-Harbaugh dynamic is a sports psychologist's delight.

Who in their right mental state ever would have predicted that the thoughtful, engaging, even-tempered Smith would click with a super-intense coach who spent the previous seven seasons running programs at Stanford and the University of San Diego? That the 49ers – a team featuring a diva at wide receiver – would develop into a disciplined, determined, unrelenting group of overachievers?

It's true. It happened. These 49ers reflect their head coach, the much-traveled former NFL quarterback who drives a dusty, black sport-utility vehicle with empty soft-drink containers in the front seat and a "God Bless America" sticker on the bumper. In other words, he might not be pretty, and he has his own NFL scars that include a limp and a left elbow that no longer straightens, but he volunteers his blood, sweat and tears.

Harbaugh is so tightly wound, so into the moment, as Smith says, his hands threaten to snap his soda cans in half. During an interview session Thursday, Harbaugh was dressed in his usual attire: black 49ers baseball cap, long-sleeved black T-shirt, running shoes that once were white and khaki slacks that were rolled above his shoelaces.

He cracked a few one-liners, smiled slyly at times and attempted to be helpful while revealing absolutely nothing. One foot tapped the other. Once or twice he thrust a hand into the air to stress a point – usually the right hand, the one with the crooked pinky finger. Another time, he almost knocked over tape recorders while reaching for the microphone.

And it works. The 49ers are listening and buying what Harbaugh is saying and selling, which from week to week consists of messages that can be corny and effective, but remain corny and effective. Playing with humble hearts. Staying loose and focused. Not overcooking the game plan for Saturday against the Saints.

A veteran of five NFL teams in 15 seasons who famously punched former Buffalo Bills star Jim Kelly for the NBC commentator's less-than-flattering critique, Harbaugh isn't averse to reaching back and relating his experiences either, including the most excruciating moment of his career: the dropped Hail Mary pass that denied his Colts a trip to the 1996 Super Bowl.

"He made a reference about how that particular game, how he walked off, thinking 'We'll be back,' and it never happened again," 49ers center Jonathan Goodwin said. "He did tell us when you get these opportunities, you want to take full advantage of them."

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