They also offered hope, after a promising finish to the 2006 season.
However, while high expectations can attract marquee free agents to rebuilding franchises, they also can get coaches fired when things go wrong.
Mike Nolan nearly learned that lesson the hard way, one reason the fourth-year coach will not complain about empty seats on the 49ers' bandwagon this offseason.
The 49ers, 5-11 in 2007 and 16-32 under Nolan, expect significant improvement with Mike Martz running their offense this year. They think Martz can help Alex Smith, Shaun Hill and the quarterback position in general. They think even moderate improvements to the NFL's worst offense could help their emerging defense challenge for a high ranking in 2008.
The 49ers think all these things, but they aren't thinking them as loudly as they might have in the past.
"Until you achieve something, it's a little bit premature to be talking about it," Nolan said this week, "and so our approach this year is going to be one day at a time, one practice, one game."
The 2007 49ers weren't the first team to believe their own hype.
The formula is familiar. Struggling team finishes strong. Struggling team spends big on free agents. Struggling team addresses needs in the draft. Struggling team emerges as a playoff dark horse. Struggling team believes the hype.
Struggling team still struggles.
"Right now, people are probably as accurate as they have ever been about us," Nolan said. "That might sound a little bit like, 'My goodness, you're not optimistic about your team.' But I am.
"It's just that a year ago, we got a little bit ahead of ourselves."
Nolan couldn't control the two things that hurt the 49ers most in 2007: losing offensive coordinator Norv Turner to the San Diego Chargers on Feb. 19, too late to find a qualified replacement; and losing Smith, the would-be franchise quarterback, to shoulder and arm injuries.
What Nolan can control is how he handles such things, and he must handle them better. And he knows it.
"I learned a lot last season," he said. "It's hard to say how much you learned because, really, in this job as a head coach, it's very different from a coordinator's job. It's totally different in a lot of ways."
The traits that made Nolan a successful defensive coordinator still apply. But the best head coaches sometimes also are skilled diplomats, a role Nolan played less than convincingly while appearing at odds with Smith last season. Having an experienced offensive coordinator on board should help, in theory, but Martz brings a strong personality of his own. The head coach must make everything fit together.
That means canceling the soap opera starring Nolan and Smith, for starters. And by all accounts, Nolan and Smith have taken steps toward that end. They have met repeatedly, and both appear eager to prevent an old story from lingering any longer.
The 49ers haven't committed to Smith as their starting quarterback, even though they drafted him first overall in 2005. The noncommittal approach makes sense because Hill played well late last season, and Smith hasn't earned the job. But the organization will win big if Smith, still not yet 24, becomes the player Nolan and personnel chief Scot McCloughan envisioned three years ago.
Smith and Nolan's relationship deteriorated last season over what appeared to be a misunderstanding fueled by poor communication. Smith publicly said he was healthy enough to play following a shoulder injury, but his performance suggested otherwise. When Smith acknowledged the obvious, that his injuries were inhibiting his play, a frustrated Nolan appeared unsympathetic. Smith ultimately accused Nolan of undermining him among players by questioning his toughness.
"Alex is a talented guy and he was steadily improving, and then the 12 healthy starts that he had, he was 7-5," Nolan said. "I don't want to get lost in his injury games, although I was disappointed in the way he handled them, but hopefully that is a learning process for him. "
Nolan, a father of four, compared the experience to parenting, only with salary-cap consequences. Sometimes there will be surprises, harsh words and hurt feelings. But the stakes are too high to withdraw.
"Rather than just say, 'He's not my kind of guy, cut it loose,' when you got cap dollars in people and you put up quite an investment in them, unless you are just 180 degrees wrong, you gotta try to make every effort to make it work," Nolan said, speaking of players in general and not Smith in particular. "The good thing about our situation is there is competition for Alex, and what I like about Alex is he is receptive to competition. He is not crumbling.
"And so there is a lot of good that I knew about Alex before that is starting to come out now, and it kind of gets me excited again."
The Web site that recently ran compromising photos of Arizona Cardinals quarterback Matt Leinart also dug up less sensational shots of Smith. One picture showed Smith, clearly in party mode, planting a kiss on a young woman's cheek.
Another photo showed the quarterback hoisting a glass in a toast with four young women at an outdoor bar.
A derogatory caption beneath the photos failed to mention that one of the women seated at the bar is Smith's sister, not some anonymous college coed. As Nolan learned last season, a person can't make informed judgments without the facts.
"Alex came into my office [Thursday], and he just kind of shook his head," Nolan said. "And I said, 'You know, Alex, this is one of those things I'm going to make a real hard line with everybody, that whatever is said, whatever questions are asked, I want everyone to consider the source, consider the question and don't act, don't just throw something off the cuff because you're angry or frustrated with something because it could be a complete lie."
The 49ers are attempting to get wiser even as they get younger.
Defensive end Justin Smith, 28, should help the pass rush. Patrick Willis is already one of the NFL's best linebackers. Manny Lawson is returning from injury. Clements is a solid corner. Bruce and Bryant Johnson should provide needed upgrades at receiver. Frank Gore and Vernon Davis are dominant players in the run game. Martz gives the offense a credible leader.
The quarterback situation remains a pivotal wild card, but at least some optimism appears justified -- in controlled dosages.
"I don't believe our guys will get ahead of themselves," Nolan said, "because they've already experienced what we've been through around here, and that wasn't good."
Mike Sando covers the NFL for ESPN.com.