Quick overview: Some years ago as part of his regular column, Sports Guy Bill Simmons wrote an NBA trade value column, where he tried to assess the top 50 assets in the league as measured by expected performance going forward (which includes age and projected improvement, peak, and decline where appropriate) and value of current contract (contracts are guaranteed in the NBA, which makes this more important than the NFL). He liked it so much (and he should, it’s a good idea) that he started doing it yearly, and on his ESPN offshoot Grantland, for the last two years, Bill Barnwell has written a similar column for the NFL. The NFL one is a little stickier for a couple of reasons: contracts aren’t necessarily guaranteed, which takes away a big punishment for poor signings: a bad player on a long, expensive contract is a major negative in the NBA, but in the NFL, he can simply be cut. A good player on a cheap contract, meanwhile, will continue to be underpaid until he is nearing the end of his contract and able to renegotiate or negotiate an extension.

Anyway, while I don’t intend to write a full column of “Best NFL Assets” (I think a more accurate term for the NFL than “Trade Value”), I did want to point out a few points in the list where I disagreed, and why I think differently about those players. My first point regards Adrian Peterson, a phenomenal talent whose value to winning games is often overrated.

(Part 1 and Part 2 of Barnwell’s column.)

The Importance of Positional Value

Barnwell rates Adrian Peterson #30 overall. I feel like that can’t be horrible, but I don’t know for sure. What I really want to address are Simmons’ footnotes:

Welcome to our biggest disagreement of the 2013 Trade Value column. I would have put Peterson in the top 12 for these reasons: (1) He’s BY FAR the best running back in football; (2) you can win 10 games with Peterson, a half-decent defense, a fairly easy schedule and Dennis Quaid playing QB for you; (3) if the Vikings DID shop him, he’d certainly fetch more than the 13th overall pick in the draft and a conditional third- or fourth-rounder (which is what Darrelle Revis cost Tampa Bay last April); and (4) if the Vikings traded Peterson, people in Minnesota would react about as well as they would if someone repainted the Mall of America green and gold. AD’s going for two first-rounders minimum, and even then, they’d never have the balls to trade him. Either way, can we make sure Peterson sees this column? I want to wager on him for the 2013 rushing title. He might write “F U B.B.” on his football cleats.

Now, Peterson is an absurdly talented running back. He might be an historically great running back; he had an historically great season last year, running with abandon for a team that had little else on offense. But two problems arise with rating him as high as #12:

1. Past performance does not guarantee future results.
2. He is a running back, and he is 28 years old.

If you were getting the Adrian Peterson of 2012, surely he would be in the top 12. Adrian Peterson was to running backs last year what J.J. Watt was to defensive linemen last year: A player playing a historically great level so far ahead of the rest of the competition that it was right to consider his performance in a tier usually reserved for quarterbacks. If you knew you could get 350 carries out of Adrian Peterson at six yards a carry every year going forward, he would be extremely valuable.

But Peterson already tore his ACL in 2011, and had a series of nagging injuries before that. He may be a physical superfreak, but he still plays a position where shelf lives are short and players break down quickly. He’s also never had a season like that before– from 2008-11 he averaged between 4.4 and 4.8 yards a carry every season.

If Peterson stayed healthy, he could put up a line like 300 carries at 5 yards a carry– and that would still be considered a disappointment if you had him as a top-12 asset. And even though that’s a disappointment, if Peterson could put up seasons like that consistently for the next six years, he might still be worth ranking as high as #12. (If he did, he would probably stick around for a 7th season, since he’d only be 506 yards behind Emmitt Smith’s career rushing record.) But between injury history, age, and the general wear and tear running backs take over their careers, the chances of that just aren’t very likely.

The other point is that he’s just a running back. Advanced NFL Stats’ expected points added isn’t a perfect statistic, but it’s a good go-to for an example like this. It’s a proprietary formula that attempts to describe exactly what it says. The list of top RBs by EPA doesn’t even have Peterson first– it’s C.J. Spiller, whom you could argue is more valuable as an asset due to his age and lower degree of wear and tear– but Peterson finished 2nd in EPA with 31.4 to Spiller’s 40.5. Even if we use Spiller’s number, 40.5 EPA would rank 19th among quarterbacks. (Tom Brady was #1 with 202.5; Matt Ryan was #2 with 178.8.) If you want another proprietary statistic, Football Outsiders has Peterson as the top RB of 2012 with 459 Defense-adjusted Yards Above Replacement, well ahead of Marshawn Lynch’s 361. The top two quarterbacks of 2012 by DYAR are Brady at 2,035 and Peyton Manning with 1,800. 459 DYAR would put Peterson 14th on the QB list.

Bottom line, running back simply isn’t important enough a position to a team’s win probability to rate one so high as an asset. Elsewhere in the column Simmons dismisses the idea that Richard Sherman is more valuable out-of-hand:

Let’s give Vikings fans a few more minutes. They’re still reeling from the fact that Barnwell thinks Seattle would be more likely than Minnesota to say no to an “Adrian Peterson for Richard Sherman straight up” trade. Just take a break, stretch your legs, maybe go to the bathroom or something.

It’s pretty funny to me that he says this, because I think the opposite is just as obviously true. Richard Sherman is 25 years old and playing one of the four or five most important positions in football at an elite level. Sherman finished last season with 54.1 EPA, still well ahead of Peterson’s mark. Sherman is not better at cornerback than Adrian Peterson is at running back, but good cornerback play is more important to winning games. The game is based around the pass nowadays, and being able to pass and stop the pass are the biggest keys to team success.

Plus, if we’re factoring in contracts, Sherman is only on the third year of a fifth-round rookie deal. He makes $555,000 this season. Peterson signed a $100 million deal with $36 million guaranteed in early 2011, and is slated to make $11.25 million in 2013. A shutdown corner for half a million dollars or a running back for more than twenty times that? I think the answer is obvious.

Last problem with Simmons’ analysis– and really, it’s a problem with Barnwell’s, too: Peterson averaged 4.7 yards per carry in 2011 before his injury, and 6.0 once he got back. Most people want to attribute this to grit, determination, and superhuman recovery powers, because it makes for a nice story. But there’s a much more tangible reason Peterson’s yards per carry jumped so much, and it has to do with a guy who only merited honorable mention in Barnwell’s column.

The Vikings drafted Matt Kalil #4 overall in 2012 to be their franchise left tackle, and he had a rookie season every bit worthy of those expectations. He projects to be even better, to continue to improve, and to anchor the left side of the Vikings’ line for a long time to come. He’s only 24, and his presence at left tackle immediately upgraded the Vikings by allowing them to slide journeyman Charlie Johnson inside to guard to replace an over-the-hill Steve Hutchinson. Improved line play is a major reason Peterson had much more success running in 2012.

Adrian Peterson is a superlative talent, but with the amount of risk surrounding his age and health, as well as the number of young premier players at important positions in the league right now, there’s simply no way he’s a top-12 asset. Personally, I’d even take Kalil over him if I was starting a franchise, but that’s just me.

On another note, welcome back to the blog after our summer hiatus. Training camp is underway, and so we’ll be posting more analyses of teams, players, and analysis as the preseason heats up and we get ready for the games. This could be one of the most exciting NFL seasons in years, as we have so many young players already playing at a high level, and I’m fascinated to see if they can extend their peak performance any higher, while also watching to see if the old guard can hold them off one last time.