Jon Kitna started six games in his first two seasons in Seattle before becoming a full-time quarterback in 1999.
McGee came from an option-oriented attack at Texas A&M, having played just one season in the West Coast offense when the Cowboys drafted him in the fourth round in 2009.
McGee won't become the starter for the Cowboys any time soon. Romo is the franchise quarterback, and he's signed through 2013 and owed $38 million in base salaries.
Kitna is signed through the 2011 season, so there is time for McGee to progress and eventually take over as the No. 2 quarterback.
"That's the natural progression," quarterbacks coach Wade Wilson said. "But Kitna has a lot of juice left, but it's time for McGee to store all this information and learn as much he can. And when that time comes, hopefully he'll be ready."
Last season, McGee was learning the NFL way of doing things and was on target to get significant playing time in the final preseason game. But he sprained his right MCL in the third preseason game versus San Francisco while throwing a touchdown pass and didn't play again.
He wore a bulky brace on the knee as he tried to get well. He got limited reps in practice during the regular season, and for the final seven weeks of the year he didn't throw a pass because the Cowboys conducted walkthrough-type practices.
"That knee injury kinda set me back, especially that last game because I was going to get to a whole lot of reps," McGee said. "That was frustrating and then at the end of [preseason] we started getting more reps on scout team, but once the [regular] season starts the third-string quarterback gets very few reps toward the end."
McGee said he learned a lot just watching Romo and Kinta go about their business. He also worked on his mechanics with Wilson and offensive coordinator Jason Garrett, a former quarterback himself.
Whether it's making subtle changes in his throwing motion, or how fast he drops back to hand off, or how quickly he finds the secondary receiver, everything is a learning experience for McGee.
The Cowboys still believe in McGee and think his strong arm and mobility will help them in the future.
The NFL is always about contingency plans. In 2008 when Romo went down with an injury, the team asked Brad Johnson to take over, and he went 1-2, including a 35-14 beatdown by the New York Giants. Those three games told the Cowboys they needed someone better to lead them in case Romo went down.
A trade was made for Kitna, who possessed a better arm than Johnson and was more mobile. The Cowboys didn't need Kitna last year but felt he could make all the throws necessary to take over if Romo were injured.
At some point, the Cowboys need to find out what they have in McGee.
Just in case.
"He's still working on his mechanics. ... [We] want him to be more consistent with his accuracy and things like that," Wilson said. "I think he's starting to get real good grasps of the offense and what the reads are, and just getting the physical reps is what he needs."
At Texas A&M, McGee became the school's all-time leader in completion percentage (59.5) and was second in total offense (7,225 yards), fourth in career passing yards (5,475) and third in rushing yards for a quarterback (1,750).
His senior season was filled with injuries, and although teams liked him, he wasn't projected as a first-day draft choice.
That's fine, because the man who is starting for the Cowboys wasn't even drafted. The top receiver on this team wasn't drafted, either.
The Cowboys are excited about players their scouting department can find and develop into stars.
McGee is far from that. However, the more reps he gets in training camp and in the preseason gives the Cowboys a chance to see what he's got.
"So this is a huge time for me," he said after Monday's organized team activities. "It's just good getting out there and getting some reps because I've been standing around for a while. It's an important growing time for me."