Is this offense a seven-touchdown juggernaut or a naught-touchdown sideshow?
Is this defense the stifling entity it has been for 5 weeks or the permissive mish-mash of the first 4?
They're probably somewhere in between.
Nobody wins, or even scores, with the third-string quarterback playing. That's doubly true if the No. 3 is a fourth-round rookie. The rotten offensive eggs they laid against the Cowboys and Giants should be explained away, then, by the predictably imprecise performance of injured starter Michael Vick, Foles and Matt Barkley.
There is a clear gap between the Eagles and the Broncos, Chiefs and, probably, the Chargers. They probably should be a 5-4 team today instead of a 4-5 squad; maybe 6-3, if the Eagles had mustered anything late against the Cowboys.
The Eagles now have beaten four teams. At the time the Eagles played them, those four teams had a combined three wins. Oakland held all three of those wins.
The combined record today of those four teams: 8-24.
The Eagles visit Green Bay on Sunday. The 5-2 Packers will try to run their winning streak to five games tonight against Chicago.
Are the Eagles ready for prime time?
They don't even know.
"We can't pat ourselves on the back and say, 'Hey we were good last week, so it's going to be a piece of cake this week,' " Kelly said. "We've got to do the same exact thing, preparing against a really good Green Bay team."
"We have to go out and prove that we can play against the top teams," said veteran linebacker DeMeco Ryans. "I can't sit here and tell you we are."
That's because Ryans knows that the Raiders are definitely not among the league's top teams. The Raiders are 3-5 and their wins have come against teams that are a combined 6-18.
But there is plenty of evidence that the Eagles are, at least, a cut above the league's lower notches.
"Call it a process," said offensive lineman Evan Mathis. "We're growing as a team, together. We, and the coaches, are learning our strengths and weaknesses. We're learning to adjust to what we're seeing."
What they saw yesterday was a Raiders team susceptible to deep passes, one terrified of losing DeSean Jackson deep, cavalier about letting Riley Cooper run free and eager for Nick Foles to try to beat them with his arm.
Jackson caught five passes for 150 yards and a touchdown. Cooper exploited one-on-one coverage for 139 yards and three touchdowns, one of 63 yards, all career bests, on five catches.
Foles was, practically, perfect: 22-for-28 and 406 yards with those seven touchdowns, which tied the league and team record. He threw no interceptions and finished with a perfect 158.3 passer rating, all in slightly more than three quarters of work.
"When Nick plays lights out, it helps," Mathis said.
When he doesn't, it hurts. Foles was brilliant in his the seventh understudy start of his 2-year career, Oct. 13 in Tampa Bay. Then Foles was anemically gun-shy in the first three quarters of a home loss to Dallas the next week: 11-for-29 for 80 yards with three sacks before leaving with a concussion.
Foles' performance against Dallas, followed by Barkley's mop-up struggles against the Giants, meant that the suddenly efficient defense wasted its best two efforts. Its starters have allowed 17.2 points per game in the last five games. It has avoided deep passes, the bane of the Birds for the past two seasons. Yesterday, they managed two interceptions and three sacks of overmatched, if elusive, Terrelle Pryor.
"It's what I expected from our defense," Kelly said. "They're getting more familiar with the scheme, they have a better understanding of where we're supposed to be. We're not getting balls thrown over our heads."
That's due, in part, to pressuring the quarterback. How porous was the Raiders' line? So porous that even converted linebacker Trent Cole had a sack. Cole had been sack-less in his 10 previous games, the longest drought of his 9-year career.
"About time," Cole said.
As sweet as this Raiders win will taste to the Eagles, they occasionally left themselves open to disaster.
"There are no perfect games," offensive coordinator Pat Shurmur admitted.
The Eagles ran into the punter at the end of the Raiders' first drive. The Eagles committed a holding penalty deep in their own territory on their own first drive. Foles floated a couple of intercept-able balls. And, frankly, the Eagles got lucky on at least two deep passes when Raiders defensive backs fell down.
For all of his weekly preparation and game-day genius, Kelly wasn't flawless, either.
He gave away three points at the end of the first half. With 2 minutes remaining, with an 18-point lead, with the ball to start the third quarter and with his defense on the field nearly twice as long as the offense, the Birds threw the ball three times, used just 61 seconds and punted to the Raiders' 25. Their tired defense sagged. Sebastian Janikowski, the most powerful kicker in league history, chipped one in from 53 yards.
In the end it mattered little, but in the moment it made a three-score game a two-score game.
Later, ahead by 36 points with less than 13 minutes to play, both quarterback Nick Foles and running back LeSean McCoy played a meaningless, disjointed series that did not include irreplaceable receiver Jackson and irreplaceable left tackle Jason Peters.
Foles was sacked on the first play of that series. Again, Foles missed the last two games with a concussion. McCoy missed four games late last season with a concussion suffered near the end of a blowout at Washington.
Sound like picking nits? Well, Kelly admitted that he knew better than to send Foles out there again to try to break the record.
"If I put Nick out there to break a record and he gets hurt, that's being silly," Kelly said.
Well, yes. Besides, with Vick still hamstrung, Foles is all Kelly has - and, truth be told, Kelly cannot know exactly what he has.
Is Foles the surgeon he appeared to be yesterday? Has Cooper, after 9 mediocre weeks, finally replaced injured No. 1 receiver Jeremy Maclin? Is this defense for real?
The answers will be better known after they visit Wisconsin.
"We've only been together since April. It's a great bunch," Kelly said. "They don't make excuses."
Excuses should not be made for them, either.
"You know, in some games, everything goes wrong," Mathis said. "In this league, things can go very wrong very fast."
On Twitter: @inkstainedretch