We are seeing now what Chip Kelly truly believes, and what he is willing to do to get the football team that he wants, and it is utterly enthralling.

The Eagles on Thursday signed DeMarco Murray - the NFL's leading rusher in 2014, arguably the most valuable player on the Dallas Cowboys last season - and they signed former San Diego Chargers running back Ryan Mathews even after speculation that they had scuttled a handshake deal with him to create room for Murray on the roster and under the salary cap. This is fun. This is fascinating. This doesn't require Marcus Mariota to be the most interesting story in the NFL.

See if you can keep up: Kelly traded LeSean McCoy to Buffalo earlier this month. He decided to replace him with Frank Gore, only to have Gore reconsider signing with the Eagles and opt for the Indianapolis Colts. Kelly then found another running back - Mathews, who rushed for more than 1,000 yards twice with the Chargers - to replace Gore. But Kelly's new presumptive starting quarterback, Sam Bradford, was Murray's friend and roommate at Oklahoma, and during his introductory news conference Wednesday, Bradford told reporters that he'd been lobbying Murray to join him with the Eagles. And here we are. There will be a test later.

The double-barreled benefit of these moves is that Kelly has assembled a versatile and, if healthy, potentially dynamic backfield of Murray, Mathews, and Darren Sproles, and he has managed to weaken the Cowboys - the defending NFC East champions - by coaxing Murray away from them.

Kelly is thumbing his nose at pro football's conventional roster-building wisdom, at the notion that a franchise can't flush away and replenish so significant a portion of its roster, but it's not just that. He's sticking it to this city's most insufferable sports rival: the haughty, entitled Cowboys. He stole away the player who was the centerpiece of Dallas' offense. It just might make up for the public panic and confusion that greeted his trading of McCoy to the Bills and Nick Foles to the Rams. It just might.

The terms of Murray's contract, as have been reported by ESPN, are interesting: five years, $42 million, $21 million guaranteed. The deal has the same amount of years and more potential money ($40 million) than the Bills gave McCoy when they renegotiated his contract, though McCoy does get more guaranteed money ($26.5 million). But the more telling fact is this: In terms of counting against the salary cap, the difference in the average annual value of the two deals is negligible. That suggests that the McCoy-for-Kiko Alonso trade wasn't as much about shedding McCoy's original, unwieldy $12 million cap hit for 2015 as it was about shedding McCoy.

Did Kelly tire of McCoy's moonwalking style of running - evasive and breathtaking but prone to plays that lost yardage? Was McCoy a skeptical congregant in Chip Kelly's Church of Culture? In the immediate aftermath of the regular season, McCoy had acknowledged the possibility that he might play elsewhere in 2015. He had a sense he might leave. There's never just one thing in situations like this.

Murray is 27, and to collect those 1,853 yards and 13 touchdowns last season, he carried the ball 393 times, the most by any NFL running back since 2006. Between his carries and receptions in the regular season and the postseason, he had 449 touches. Just five backs in league history have had more in one season. There is ample evidence to suggest that so heavy a workload will exact a toll from Murray that will make him a bad long-term bet.

But with Mathews and Sproles joining Murray, Kelly can spread the ball around, mitigating the pounding and attrition that each running back would have to withstand. He also appears to approach his player-personnel decisions as if he were still recruiting at Oregon, presuming that most if not all of his players will be around for four years at most.

Murray, Mathews, Bradford, Alonso, cornerback Walter Thurmond - each of them has suffered serious injury recently or wear-and-tear over the course of his career. All of them have health histories that would likely give a more conservative team-builder pause. Yet Kelly has plowed ahead, banking that the sports-science and nutrition programs he has instituted will help keep these heretofore fragile bodies intact and that all 53 men on the active roster will buy into his system.

That buying-in, that complete acceptance of Kelly's philosophies, gets to something else that's at work here, too. None of the players whom Kelly has acquired during this spree of trades and signings has more than five years of NFL experience. That benchmark of five years is no coincidence, based on something Thurmond, who played for Kelly at Oregon, said before last year's Super Bowl while he was a member of the Seattle Seahawks.

"When you have guys who can buy into the program and are kind of naive to the business aspect, they give you their all," Thurmond said. "When you have guys who are six, seven, eight years into the game, they know how it is. It's a job for them. Something's missing, a little bit. They're kind of hip to what's going on."

So the weirdest, wildest offseason in Eagles history rolls on with Chip Kelly at the wheel, and the NFL draft is still a month and a half away. Nothing is finished yet. It's still early in the process, really.

Can this strategy work? We'll begin to find out after Gov. Christie calms down enough to reopen the Philadelphia-bound lanes of the Walt Whitman Bridge.

@MikeSielski