"We're both real guys - no ego," Schneider said. We "want to be very successful and do whatever we can to be competitive in anything we do - whether it's Pete throwing the ball 50 yards in the pregame or us competing in cornhole when we first met."
Unlike the Eagles, though, the Seahawks chose their head coach before their GM when they went about turning over the franchise in early 2010. Carroll, 62, was hired first, sat in on interviews, and was part of the decision when the then-38-year-old Schneider was chosen to be his copilot.
Schneider said he had met Carroll years earlier, when he was working in various NFL personnel departments and would visit Southern California to ask the coach about prospects. Carroll didn't recall him when they first met during interviews.
"I give him crud," Schneider joked.
But something clicked, and more than a partnership was formed.
"He really wanted to make it a special relationship. It just worked out great. We just spent so much time together," Schneider said. "Listening to music and studying, getting to know who he was as a person, first and foremost, and his philosophies. His scheme, how he wanted to play, and how we wanted the team to look."
Carroll has final say, but it's different from the final say that John Elway has as the Broncos' executive vice president of football operations. Elway is at the top of the pyramid, but his involvement isn't at the ground level along with coach John Fox.
Figuring out who has final say with the Eagles has been a more difficult task, although Kelly said last August that he had final say over the 53-man roster. Roseman seems to be in charge of the offseason - namely, free agency and the draft - but Kelly, of course, will be just as involved.
Both will say any preoccupation with who has final say is pointless as long as they work together to build a championship team. Schneider agreed.
"I think if you have two people that have one goal in mind, then it doesn't matter," he said. "But I think there can be some situations where there's total disagreements, where there could be disagreements and one person has to be able to make a decision."
When Brian Billick was head coach of the Ravens, Ozzie Newsome was his GM. He said there was nothing substantive written in their contracts that one had final say over the other. Somehow they made it work and won a Super Bowl in 2001.
"Ozzie and I had the relationship that we understood that the first time we ever had to go to [owner] Steve Biscotti and say we don't agree, you've got to resolve it, we both should have been fired," said Billick, now an analyst for NFL Network and Fox. "At one point, either you convince me or I'll convince you."
Billick said that he and Newsome - still the Ravens GM - used to "scrimmage constantly" about players. But the respect they had for each other and their congruent visions for the team helped steer them through thorny times.
"You can have all the input you want, but at the critical moment there has to be that singular voice," Billick said. "If you don't have that understanding in that relationship you've got no chance, and about three-quarters of the league doesn't have that relationship."
It's unclear if Kelly and Roseman have ever had an impasse. They had met only a few times before the Eagles interviewed the Oregon coach last January. Owner Jeffrey Lurie made the final decision, but Roseman had great influence.
When Lurie fired head coach Andy Reid a year ago but kept Roseman, he said he wanted the coach-GM power structure that had been successful for other organizations like the Seahawks.
It's hard to argue with the early results. The Eagles rebounded from a 4-12 record in 2012 to finish atop the NFC East at 10-6 in the first year of the Kelly-Roseman pairing.
The Seahawks went 7-9 in 2010 and 2011, but the roster was undergoing a major change. The Super Bowl team that finished 13-3 this season after going 11-5 in 2012 has only three players who were on the 53-man roster before Carroll and Schneider arrived.
Many of the players they've acquired have been home runs. Safety Earl Thomas, tackle Russell Okung, and linebacker Bruce Irvin were first-round draft picks. Quarterback Russell Wilson was snagged in the third round. Cornerback Richard Sherman and safety Kam Chancellor were poached in the fifth.
"We've had a tremendous run in the lower rounds," Carroll said. "In these past few years, John has done a tremendous job of getting guys in the fifth round."
Running back Marshawn Lynch, linebacker Chris Clemons, and wide receiver Percy Harvin came in trades. Defensive linemen Cliff Avril and Michael Bennett were free-agent additions this offseason. The hits go on and on.
But there were disagreements that needed to be resolved.
"We just sit and work through it," Schneider said. "We'll just sit, and we'll watch more tape and just continue to talk. We just keep going back and forth."
Carroll's mantra is "always compete." Schneider said competition fuels their relationship. A thirst to win seems to drive all successful team builders. Elway said that being a decision maker is no different from being a player.
"To me," Elway said, "the common denominator is competitiveness and wanting to win."