DENVER -- Vic Beasley Jr. was asked how it felt to beat the reigning Super Bowl champs in their elevated backyard. "Everyone's happy," he said. "Everyone's excited."

Then, channeling his inner Belichick: “And now it’s on to Seattle.”

And maybe then we’ll know. The Falcons are 4-1, having beaten last season’s Super qualifiers back-and-back and rather handily. But they were 5-0 last year – I know you’re tired of hearing it; I’m tired of writing it – and we were charting the probability of them being the NFC’s No. 1 seed. Fool me once …

After Sunday’s display of power and poise in a famously difficult stadium, Dan Quinn still had to field something of a prosecutorial question: After what happened last year, he was asked, what makes you think you’ll be able to keep it up?  Quinn's response: “I recognize the question, and the answer is it's a different outfit. I recognize where you're going with it, but it’s a different group. We’re a mentally tougher group than we were. We have real ability to understand how we have to reset to get ready to go right back to that process."

There’s a part of me – the part that just saw Quinn’s Falcons beat John Elway’s team 23-16 – that wants to say, “Know what? He’s right.” Then I note that Denver’s quarterback wasn’t Peyton Manning or Brock Osweiler or even Trevor Siemian. It was Paxton Lynch, a rookie backup. Here we stipulate that Siemian, the usual starter, isn’t to be confused with Elway – the Broncos’ offense ranked 21st entering the game – but still: No team is as good without its No. 1.

Once the Falcons got ahead, which happened after three minutes and 42 seconds, there was never a clear and present danger of them falling behind. The defense pressured Lynch the way an NFL defense is supposed to pressure a rookie, but it induced only one turnover – an overthrow that had “Intercept Me” all over it. Ricardo Allen did, and the Falcons soon scored the clinching touchdown.

There can be no faulting the Falcons’ performance Sunday. They were the better team by some distance. They did what they had to do and did it with dispatch. Not so long ago, a day that saw Julio Jones catch two passes for 29 yards would have yielded a thudding loss, but Kyle Shanahan’s offense found alternatives. Even this Shanahan critic had to concede: This was his fourth in a string of nicely managed games.

For all of that, there’s another part of me that wonders: Is this really real? Last season’s 5-0 likewise looked rather dynamic, the victories over Dallas and Houston especially. I’ll concede that the offense is better-rounded – Devonta Freeman and Tevin Coleman are Mr. Outside and Mr. Way Outside, and the line is quite good – but I still wonder about the defense. It had its best game Sunday, but how much of that was due to the identity of the opposing quarterback?

We should know more after Sunday in Seattle. Yes, we saying the same this time last week, but at some point these Falcons will get an asterisk-free test. The guess here – and remember, I’m the guy who called them “a bad team” after the ignominious Tampa Bay opener – is that they’re probably not of Super Bowl timber, which isn’t to say they can’t win the NFC South.

Then again – and how many times can I type “then again”? – they were sitting pretty last October. I do believe there’s something to what Quinn says. A team that craters once is apt to be on its guard against doing the same, is it not? Once bitten, twice shy.

“Give them credit,” Broncos coach Gary Kubiak said. “They’re a really good team.” (Shortly thereafter, he was hospitalized for flu-like symptoms. I ascribe no connection to the game itself.)

For the past four weeks, the Falcons have been a really good team. And now it’s on to Seattle, where Quinn once worked, where greater truths stand to be revealed.