IRVING, Texas - After the home-opening loss to New York last September, a lot of people came to the conclusion that Tony Romo was a finished product, that he couldn't help himself sometimes.

Some of the decisions he made that night looked awfully familiar. His third-quarter pop fly, intercepted by Kenny Phillips, was as routine as the one he had thrown to Baltimore's Ed Reed in the Texas Stadium farewell game the previous season. In his weekly press conference a few days later, Romo acknowledged the need to play better, but said his numbers would even themselves out over the course of the season.

"I'm better than you think I am," he promised a disenchanted colleague. It didn't take long at all for Romo to prove himself right. Whereas history suggested December would be his worst month, Romo was actually at his blandest in the first quarter of the year, throwing just four touchdowns against four interceptions.

Things changed in the fifth outing of the year, with the emergence of Miles Austin. Over the season's final 12 games Romo threw 22 touchdowns against only five interceptions, meanwhile limiting himself to only four lost fumbles despite taking a career-high 34 sacks. He even ended up breaking his own team record for passing yards with 4,483.

As much respect as Romo deserved for his play the first two-and-a-half seasons he was the Cowboys' starter, 2009 stands as his best effort. Playing with an often-explosive running game and the NFC's toughest defense, Romo took fewer chances, but still made big plays. His yards-per-attempt average (8.2) was the second highest of his career, and his quarterback rating (97.6) was a personal best.

The Cowboys are counting on a few things next season, now that expectations are back to Super Bowl-or-bust. The defense has to be just as staunch as it was toward the end of '09. The entire roster needs to be relatively healthy once again. But maybe most important, the Cowboys cannot afford for Romo to backslide.

Most players aren't still progressing at age 29, but Romo proved last year he was capable of getting better. He has accepted Jason Garrett's day-by-day improvement maxim, and made it reality. As he continues to work on some of the technical aspects of the position, the Cowboys are confident his experience in the system will translate to even better decision-making.

The importance of the continuity between Romo, Garrett and quarterbacks coach Wade Wilson cannot be overstated.

"They can maximize the benefit of working with each other going into their fourth season," Jerry Jones said of Romo and his support group. "That's starting to get real good right there. We are starting to be among the minority of the clubs that have that level of stability.

"That will make Tony better. He will be better just because of that."

Only three teams in the NFL - Indianapolis, Philadelphia and New Orleans - have had the same starting quarterback and play-caller in place longer than the Cowboys. Go figure, two of them met in the Super Bowl last season.

The Cowboys and five other teams (Cincinnati, Pittsburgh, Jacksonville, San Diego and the New York Giants) have had the same quarterback and play-caller duo since 2007. It's no wonder they combined for a record of 58-38 last year. Getting ready to pick the division winners next September? This is a good place to start.

Take the league's best, Peyton Manning. Talented and smart as he was to begin with, it's hardly a coincidence he's become the league's sharpest player, and master of his own offense. Manning has had Tom Moore as coordinator his entire 12-year career.

"I think (stability) is important at all positions throughout a football team, but particularly the quarterback position," Garrett said. "Tony's been in the same system now for three years. It's amazing how much you can learn about the system, even beyond the basic things - understanding the nuances and really taking it to the next level."

It's a fortunate step in the right direction for the Cowboys organization. Garrett has flirted with head coaching gigs in Baltimore, Atlanta, St. Louis and Detroit, but his fourth season as Cowboys offensive coordinator will tie the longest such stint of a play-caller since Jerry Jones bought the team. Ernie Zampese served four years tutoring Troy Aikman from 1994-97, running much the same offense Norv Turner had in place from 1991-93. The Cowboys switched to Chan Gailey's system in '98 and '99, before Aikman played the last football of his career under coordinator Jack Reilly in 2000.

From there, the Cowboys pinned their hopes on Quincy Carter, who had the offensive coordinator shuffle as one of several built-in excuses during his Cowboys career. He went from Reilly's offense, in the Coryell-Zampese-Turner mold in 2001, to Bruce Coslet's version of the west coast system in 2002, to Sean Payton's passing tree in 2003, never really getting the hang of any of the three playbooks.

Though I've heard Romo say before it's not all that tough to learn a new coach's system, he is undeniably blessed to still have Garrett monitoring his progress. But how can progress be measured with Romo turning 30 on April 21?

Improvement from here on out, or evidence he's turned a corner, would be making sure the ball security from 2009 is not one day seen as the statistical outlier of his career. Until he repeats last year's performance, though, that's what it is. His interception percentage was 1.6 last season, almost half his previous low of 3.1 percent in 2008. That number has been trending downward his entire career, from 3.9 percent in those 10 starts in 2006, to 3.7 percent in '07, to 3.1 percent in '08.

Cutting his likelihood for minus plays in half was a major step in Romo's development. The key to meeting expectations in 2010 will be not taking that same step backward.

"I think he's getting a better understanding every day of what we're trying to do," Garrett said. "He's getting a better understanding of how to function within game situations and he's playing better and better.

"He's made a lot of progress and there's still a long way to go."