Romo's 19-2 record in November gives him the best winning percentage of a quarterback in the Super Bowl era with a minimum of 15 starts in that month.
As good as those numbers are -- New England's Tom Brady is 29-10 in November for those keeping score -- they are also something of a curse because Romo's record in December and January games is 8-10.
Romo has called his November success a coincidence more than anything else, which is why he dismisses the 8-10 record in the same manner.
"Stats, in that regard, they come and go with whatever's in vogue recently," said Romo, who has 23 touchdown passes and 21 interceptions in December/January.
Yet that mark hangs around Romo's neck in a way that his NFC East contemporaries' records do not. Eli Manning is 16-18 in regular-season games in December and January for the New York Giants. Michael Vick owns a 13-15 late-season regular-season record.
What gets overlooked, however, in the dissection of Romo's record is the Cowboys' opponents from 2006 to 2009. Seven of the 10 losses came against teams that made the playoffs and only one had a losing record. Only one defense ranked outside the top half in the league and six were ranked in the top 10.
In 2006, the Cowboys lost to the New Orleans Saints, who made it to the NFC Championship Game; the Philadelphia Eagles, a playoff team; and the 3-13 Detroit Lions, who owned the 28th-ranked defense that year.
In 2007, they were 2-2 with losses to Philadelphia and the Washington Redskins. The Redskins loss came in part because Wade Phillips pulled the starters in the second half with home-field advantage wrapped up.
In 2008, the Cowboys lost to the league's top three defenses in Pittsburgh, Baltimore and Philadelphia to finish 9-7 and miss a playoff spot by a game.
In 2009, the Cowboys lost to the New York Giants and the 13-3 San Diego Chargers.
"I just think that's probably for somebody else to try to decide that stuff," coach Jason Garrett said when asked of the two Romos. "Tony's played well throughout his career in a lot of different months. He's played well against a lot of different opponents in a lot of different places. He and our football team have to take this next challenge against Arizona really as our sole focus and not worry about what happened in November."
After that loss to the Chargers, however, Romo went on a three-game December/January winning streak.
The Cowboys ended New Orleans' run at a perfect record with a 24-17 win at the Superdome on Dec. 19 and followed that with shutout victories against Washington and Philadelphia to win the NFC East title for the second time in three years.
In that stretch, Romo had two 300-yard passing games, four touchdowns and two picks. He completed 67 percent of his passes.
Only Green Bay's Aaron Rodgers (127.7), Brady (105.1) and New Orleans' Drew Brees (103.6) have a better passer rating than Romo. His 21 touchdown passes are fifth-most in the NFL. His completion percentage (64.5) is fourth-best.
In the last two games, he directed game-winning drives in overtime and at the end of the fourth quarter.
"He's playing well for us right now, creating a lot, making a lot of plays for us," tight end Jason Witten said. "That's been pretty huge for us. He's going to need to continue to do that. But he's got high expectations. He knows his standard for what he wants as success and this team to be is so high. I think all of us piggyback off that and we know what this month means."
And no one knows more than Romo.
"You're defined by winning and losing," Romo said. "Super Bowl is really what you're defined by at the position and that's what you're always trying to get to."
Todd Archer covers the Cowboys for ESPNDallas.com.