You’d think this national obsession with analyzing the NFL draft would produce someone who actually knows all that will happen when the three-day selection show kicks off in Chicago on April 30.

You’d be wrong.

“There will be a number of surprises, particularly in this draft because so many guys are so close in talent,” Vikings General Manager Rick Spielman said. “I know just reading through some of the mock drafts, there are some names we’re considering at No. 11 that haven’t even been mentioned. And then there are names attached to us that I don’t think we’d even consider at 11.”

Of course, one should remember it is draft season. Sleight of mouth, not full disclosure, is the more sensible method of communication for the 32 men entrusted with the highly competitive duty of restocking an NFL team’s 53-man roster.

“I talk to a lot of people, but I’ll be frank,” draft analyst Charles Davis said. “I don’t know that I trust anybody right now. I don’t mean that they’re lying, but no one wants to tip their hand. So we shall see what happens.”

Indeed, we will. Here are some of the story lines to follow:

Finding Mariota’s home

Florida State’s Jameis Winston and Oregon’s Marcus Mariota — the past two Heisman Trophy winners — are 1-2 at QB. Or 2-1, depending on your preferred tastes. No. 3 is a distant bronze medalist that presumably will be decided outside of the first round.

Winston is believed to be Tampa Bay’s target at No. 1 overall. But Andrew Luck he is not. Immaturity and character issues make him a risk, while a much greener skill set will require more patience than you’ll find in most 21st century NFL cities.

Mariota is just as raw and equally talented. Maybe more talented, according to ESPN analyst and noted film junkie Ron Jaworski, who argues that Tampa Bay should take Mariota No. 1.

Tennessee owns the second pick and might welcome that scenario since Winston is a better fit. If Winston is off the board, the Titans have options that will shape the top half of the draft.

They could take a leap on Mariota as their quarterback of the future behind Zach Mettenberger. They could pick the best non-quarterback. Or they could trade the pick to the highest and most desperate bidder.

ESPN analyst Bill Polian, the Hall of Famer and former NFL general manager, said teams targeting Mariota need to assume he will be gone within the top three picks. Jacksonville has the third pick. The Jets at No. 6, Chargers at No. 17 and particularly the Eagles at No. 20, with former Oregon coach Chip Kelly salivating, are among the teams believed to be interested in trading up.

Polian isn’t buying the speculation that Tennessee would accept a veteran quarterback, such as San Diego’s 33-year-old Philip Rivers, as a major piece in a trade for the No. 2 pick. Not when the Rams got three No. 1 picks and a No. 2 in the Robert Griffin III trade only three years ago.

“Why wouldn’t that be the benchmark?” Polian asked. “The price to move up to No. 2 would be pretty darn high, I would think.”

But this is the NFL. Teams that don’t have quarterbacks usually take big swings until they finally connect.

No-risk receivers?

“I think the top three wide receivers are the safest picks in the draft.”

In your life, did you ever think you’d hear anyone say those words? But that’s what NFL Network analyst and former NFL scout Daniel Jeremiah had to say about Alabama’s Amari Cooper, West Virginia’s Kevin White and Louisville’s DeVante Parker.

“Normally, you’re talking about boom or bust when you’re taking receivers in the first round,” Jeremiah said. “Especially in the top 10.”

The evolution of the college game has helped the NFL evaluate receivers more accurately. Or, as Jeremiah put it, “You’re not having to guess as much.”

Twelve receivers were taken in the top two rounds last year. ESPN draft analyst Todd McShay believes 10 more will go in the top two rounds this year.

Fellow ESPN draft analyst Mel Kiper Jr. projects three in the top 10: Cooper to Oakland at No. 4, White to the Bears at No. 7 and Central Florida’s Breshad Perriman slipping ahead of Parker at No. 10 to the Rams based on a pro day that included two sub-4.3 40-yard dashes.

Spielman could take Parker, reuniting him with quarterback Teddy Bridgewater, but count the Vikings GM among those who see tremendous depth at receiver.

“Everybody talks about the top three receivers, but there are some significant receivers below that who are going to be pretty good players,” Spielman said. “There are a lot of guys who maybe the media aren’t talking about.”

Best of the rest

Return of the RBs? The consensus is we will see the first running back selected in the first round since Cleveland made Trent Richardson a monumental bust at No. 3 in 2012. Will it be Wisconsin’s Melvin Gordon, the healthiest of the top two backs, or Georgia’s Todd Gurley, who has drawn comparisons to Adrian Peterson, except he hasn’t run for 2,097 yards since tearing an ACL last fall. Kiper has Gurley going to Cleveland at No. 19. Great value or greater mistake?

Rushing into the top 10: Two quarterbacks and three receivers could make up half of the top 10. But pass defense is still a big deal in a passing league. Kiper and McShay have four edge rushers going in the top 10. The Bears at No. 7 are in a bit of a pickle, albeit an enviable one. Do they take a receiver to replace Brandon Marshall and pair with Alshon Jeffery? Or do they finally tend to that woeful defense and grab one a top edge rusher such as Clemson’s Vic Beasley or Missouri’s Shane Ray?

Trade flurries or calm? Significantly higher salary caps and limits on rookie contracts are only part of the reason for the trade-heavy, action-packed first rounds of the past three years. “You also have a lot of new people in GM positions bringing new philosophies and wanting to be aggressive,” Polian said. The Browns under Ray Farmer made three trades in the first round a year ago. Spielman has made two first-round trades — one down and one up — in two of the past three first rounds. But will the action continue this year? Polian has his doubts beyond a potential blockbuster move up for Mariota.

“This is a strange draft,” Polian said. “You have a lot of players, including the two quarterbacks at the top, that are bunched together. There’s not a lot of separation, at least in my mind, between these players. That would lead you to believe that there might not be a lot of movement.”

For Spielman, part of the allure of trading back into the first round is securing the fifth-year option that comes only with first-round picks. But even Spielman might be hamstrung with only seven picks — his fewest in four years as general manager — including no sixth-rounder and two seventh-rounders.