The golden rule at Winter Park is nonnegotiable. A draft class cannot be fully evaluated until after three seasons.

So there will be no celebration of the Vikings' 2012 haul until January 2015. At the earliest.

To rejoice now would be premature, like declaring a Las Vegas trip a success after a hot 30-minute blackjack run.

"What if all those guys we picked last year come back in 2013 and stink it up?" asked General Manager Rick Spielman.

That, of course, is not the expectation. Not with a group whose talent and hunger paid immediate dividends. So even with the three-year rule in place, those within the Vikings organization have no problem expressing unbridled enthusiasm about the momentum built through last year's draft.

It was a weekend that included 10 picks and four trades, a draft that delivered difference-making starters on offense and defense in Round 1 (Matt Kalil and Harrison Smith); a Pro Bowl steal in Round 6 (Blair Walsh); and plenty of promising complementary parts throughout (see: Josh Robinson, Jarius Wright, Rhett Ellison and Robert Blanton).

Sure, we may only have one season of on-field results to assess. But the internal hunch is that last year's draft may long be looked at as a landmark turning point.

Said director of college scouting Scott Studwell, entering his 22nd season in the player personnel department: "As long as I've been doing this, that class is one of the best if not the best that we've had here. A lot of things just clicked."

So how did it all come together?

And which key elements will the Vikings hope to find again when they charge into another critical draft this weekend?

Here's our look back …

Day 1: Having a plan, attacking with purpose

In the final days before last year's draft, two certainties emerged. First, the Vikings were set on making Kalil their top pick. Yet even with that, Spielman also was growing increasingly eager to plunge into one of his favorite activities of the weekend: trade talks.

Convinced Kalil was a can't-miss future Pro Bowl player, Studwell feared Spielman's urges to wheel and deal might interfere with the opportunity to land the superb left tackle.

So before leaving Spielman to his fun, Studwell made sure to reassert his stance: Kalil was a must get, no matter what kind of chatter caught the GM's ear.

"But what if we were to get some crazy, RG3-type compensation offer for that No. 3 pick?" Spielman asked, mostly trying to instigate Studwell.

Studwell didn't budge.

"Don't [bleep] this up," he said. "Seriously. Get Kalil."

Spielman laughed.

"Oh, no. I was serious about it," Studwell said. "One hundred percent."

As it turns out, Spielman and the Vikings danced gracefully through the draft's first night. Not long before the draft began, Spielman convinced Cleveland GM Tom Heckert that another team was scheming its way up to the Vikings' slot at No. 3 to nab running back Trent Richardson, the player the Browns most coveted.

We might never know whether that was a legitimate possibility or sly posturing. But somehow Spielman plucked four picks from Cleveland without giving up anything at all. The Vikings simply slid from No. 3 to No. 4 while gathering additional selections in Rounds 4, 5 and 7.

In a draft full of exhilarating moments, that might have provided the biggest jolt.

Said assistant GM George Paton: "That started us off with really good energy."

The Vikings had gained more than just a good feeling, however. They had collected valuable draft currency, enough to buy flexibility and peace of mind.

So after picking Kalil, they zeroed in on the player they always had coveted with their second pick: Notre Dame safety Harrison Smith.

The Vikings debated holding still until their next pick — at No. 35, early in Round 2 — to grab Smith. But that selection would not come until Friday evening. And the thought of waiting frazzled Spielman.

"It would have been a sleepless night," he said.

So the Vikings reassessed the "hot spots" where Smith conceivably could slip away, then plowed through trade offer calls to teams in the early 20s — Detroit at 23, Pittsburgh at 24, Denver and Houston at 25 and 26.

Eventually, Baltimore latched onto an offer that enabled the Vikings to jump from No. 35 to 29 while surrendering a fourth-rounder.

Harrison Smith was all theirs.

"I'm not sure we make that move back up without those picks we got [from Cleveland]," Paton said. "But we all started talking. Why even risk losing Harrison? We have the ammo. Let's go get him. Because after Harrison, we didn't think there was any other safety who could come in and start for us."

Day 2: A lesson in patience

After drafting Smith, the Vikings were left with only one Friday selection — a third-rounder, pick No. 66.

With a huge need to upgrade his passing offense, Spielman watched as the first run on receivers began. Brian Quick, Stephen Hill, Alshon Jeffery, Ryan Broyles and Rueben Randle were all taken in Round 2.

And as that receiver run continued, the Vikings began eyeing three potential cornerback targets.

But then at No. 62, Green Bay grabbed Vanderbilt's Casey Hayward. Three picks later, Montana's Trumaine Johnson landed with St. Louis.

While securing Kalil and Smith on Day 1 had been ideal, the Friday board had not broken perfectly.

Anxiety surged.

"But," Spielman said, "that's the other big part of the draft — the patience. And making sure you stay in 'Don't panic' mode."

Missing out on Hayward and Johnson stung some. But Studwell recalled draft advice from former coach Dennis Green: "You've got to like a lot of guys."

In the big picture, the Vikings still really liked and valued a 21-year-old from Conference USA, a young playmaker with good size, elite speed and plenty of upside.

From New York, former Vikings star Anthony Carter made the official announcement: "With the 66th pick in the 2012 NFL draft, the Minnesota Vikings select Josh Robinson, defensive back, Central Florida."

Day 3: The passion priority

When Saturday arrived, the Vikings still owned nine picks in the final four rounds. Eventually, they made trades with Detroit and Tennessee to accumulate selections for 2013 while also filling out their 2012 class.

The game plan for the middle-to-later rounds revolved around finding potential, guys who could be immediate special teams contributors while working their way up the depth chart.

With that in mind, Spielman zeroed in on players with obvious passion, which is why the selections of Wright, Blanton, Audie Cole and especially Ellison resonated.

Over the years, Spielman has scrutinized his draft mistakes far more than he has ever celebrated his victories. He says he has learned to place greater value on guys to whom football means the most.

And sure, shortly after being picked in Round 4, Ellison asserted on a conference call that he never expected to be drafted at all. But the Vikings believe he might very well go down as the most underrated selection of a potentially special draft.

In addition to his blocking ability and versatility, Ellison's work ethic, selfless attitude and enthusiasm surfaced during his interview at the combine followed by a more intimate visit with the Vikings at Southern California when the team went to lock in on Kalil.

"You can see that passion on film. You can get that from talking to your sources," Spielman said. "We get it from our psychological testing. But then you can really nail it down once you sit there and look the kid square in the eye. … You wait for that little bit that really resonates."

The exclamation point: late-round luck

No pick from the Vikings' 2012 draft created more immediate head scratching than the sixth-round selection of Blair Walsh.

Really? With so many holes, the Vikings were using a sixth-round pick on a kicker? And not just a kicker, but a guy who missed 14 field goals as a Georgia senior? At a position where 15-year veteran Ryan Longwell had been ultrareliable?

Yet arguably no other player in the Vikings' 2012 draft class was more important to last season's playoff surge. Walsh's rookie synopsis: A perfect 10-for-10 on field goals from 50 yards or longer. Two game-winners. Fifty-three touchbacks on 86 kickoffs. All-Pro honors.

"Not even we could have foreseen all that," Studwell said. "We obviously had our reservations. But we could also see his talent. So I guess I'd call it an educated guess."

With a fortuitous twist.

Leading to the draft, the Vikings talked extensively about finding an upgrade over Longwell. But they only wound up with Walsh after the two other kickers in their sights — Texas A&M's Randy Bullock and Missouri Western State's Greg Zuerlein — came off the board at picks 161 and 171 respectively.

The Vikings never had to unveil their choice on which kicker they liked most, holding their breath until Walsh was officially theirs at pick 175.

And the rookie exploded onto the scene, kicking his way to Hawaii for the Pro Bowl after helping the Vikings to the playoffs.

Walsh proved to be another sparkling draft gem in an April 2012 weekend full of them.

Said Studwell: "The whole draft just flowed well. It felt right. We did a great job of evaluating and then moving around to maximize that. And we wound up with a class that everyone felt terrific about."

Those feelings, it is hoped, will last until the three-year evaluation milestone and beyond.