When the Miami Dolphins signed 2010 fourth-round pick David Arkin off the Cowboys' practice squad 10 days ago, Arkin became the latest name in a long line offensive line picks that failed to work out for the Cowboys. Outside of the two first-round OL picks, Tyron Smith and Travis Frederick, the Cowboys have invested 17 draft picks into the offensive line since 2000. Only two of those picks, Andre Gurode (2nd round, 2002) and Doug Free (4th round, 2007) worked out favorably for the Cowboys.

A "hit rate" of two out of 17 raises questions about the Cowboys' scouts ability to recognize what makes an NFL-caliber offensive lineman. And this is especially worrisome as there's a good possibility that the Cowboys could draft another offensive lineman next year.

Three years ago, after a group of industrious BTB bloggers painstakingly decoded a video shot in the Cowboys draft room that showed the Cowboys draft board, we compared how the Cowboys had graded the O-line draft prospects with where those same prospects ended up being drafted. We concluded that the Cowboys appeared to be grading O-line prospects too low relative to where they were actually drafted in the 2010 NFL draft.

What we found was that the Cowboys didn't have a single lineman with a second-round grade, yet three were taken in the second round. Even more troublesome: of the 12 lineman on the Cowboys board without a first-round grade, nine (or 75%) were graded at least one round lower than where they were eventually picked, one (Jon Asamoah) was graded in line with where he was picked and two (Mitch Petrus and Sam Young) were graded higher than where they were picked. Here's what I concluded at the time:

In economic terms, what we have here is a seller's market: In a seller's market there are more buyers than sellers, and high prices result from this excess of demand over supply. Translated to the NFL, this means that there are not enough linemen to meet the demand of NFL teams. As a result, you likely have to overpay in terms of draft picks to get one. The Cowboys' draft grades may be correct in terms of player quality/potential and fit with the Cowboys - or they may be incorrect, I'm in no position to judge. But it doesn't matter one bit. If you're grading 75% of the players (outside of first-rounders) below where they'll get picked, the likelihood of getting a lineman by sticking to your draft board is pretty slim. Quality linemen are a scarce commodity. Other teams are 'paying' for their O-linemen with higher draft picks. If the Cowboys want to fix their line, they'll likely have to do the same. We only have one draft board to go against, but the history of the Cowboys drafts suggests that the 'mis-grading' of O-line talent is a persistent issue for the Cowboys.

This year, thanks to rabblerousr's work in decoding the 2013 draft board, we can repeat that exercise and see whether anything has changed. Here's how the Cowboys graded the offensive linemen on their draft board relative to where those players were actually picked in the 2013 draft.

Round Pick Team Position Position Cowboys grade Difference

1 1 KC Eric Fisher T 1 0 1 2 JAC Luke Joeckel T 1 0 1 4 PHI Lane Johnson T 1 0 1 7 ARI Jonathan Cooper G 1 0 1 10 TEN Chance Warmack G 1 0 1 11 SD D.J. Fluker T 2 -1 1 19 NYG Justin Pugh G 2 -1 1 20 CHI Kyle Long G 3 -2 1 31 DAL Travis Frederick C 2 -1 2 42 OAK Menelik Watson T 3 -1 3 72 NYJ Brian WInters G 4 -1 3 77 MIA Dallas Thomas G 4 -1 3 89 HOU Brennan Williams T 5 -2 4 107 TEN Brian Schwenke C 5 -1 4 109 GB David Bakhtiari T 4 0 4 116 ARI Earl Watford G 5 -1 4 121 IND Khaled Holmes C 4 0 5 141 NYJ Oday Aboushi T 5 0 5 168 BAL Ricky Wagner T 5 0 6 176 HOU David Quessenberry G 7 -1 7 240 CIN Reid Fragel T 5 2

What you can see here is that the Cowboys got the grades for the top five picks right. However, that in itself is not an achievement - even the most grading-challenged draftniks had those five guys going in the first round.

Where it gets really worrying is after those top five. Of the 16 players with a second- to seventh-round grade, 11 (69%) are graded lower than where they ended up being picked. And what is of particular concern is that string of red numbers from the middle of the first round all the way through the middle of the fourth. In that range, every single prospect (including Travis Frederick) was picked at least a round higher than where the Cowboys had graded him.

What this means is that if the Cowboys were following their board and weren't going to "reach" for a prospect, there was not a single offensive lineman they could have drafted before the end of the fourth round.

Further compounding the issue is that there were another six mid-round linemen whom the Cowboys didn't even have on their draft board.

Mid-round draft picks not on the Cowboys 2013 draft board Round Pick Team Player Position Games played 2013 3 65 DET Larry Warford G 9 3 75 NO Terron Armstead T 2 3 86 IND Hugh Thornton G 10 4 108 CAR Edmund Kugbila G 0 4 113 STL Barrett Jones G 0 4 122 GB J.C Tretter T 0

The Cowboys probably had very good reasons for not having any of these players on their board, and since we don't know what those reasons were, it's a waste of time to argue about whether they should have been on the board or not. Fact is that by excluding these players, the Cowboys further limited their options, which were already limited to begin with due to their systematic undergrading of mid-round O-line prospects.

In 2010, 75% of the O-line prospects without a first-round grade were graded at least one round lower than where they were eventually picked. In 2013, that number remained at about the same level with 69%. That's not a coincidence. That's a systemic issue.

For all I know, the Cowboys' draft grades may be right. But if demand outstrips supply, you've got to accept that you'll have to pay a premium for a quality lineman and factor that in to your draft board. Otherwise you run the very real risk of wasting yet another draft pick on a lineman who won't pan out and who you'll have to replace with an expensive free agent.

It's important to understand that undervaluing or undergrading per se is not really an issue, as long as you then take the market environment into account and recognize that other teams are either grading higher or willing to spend more. So if you really need a center, you may have to accept that the guy with the second-round grade on your draft board will not be there in the second round anymore, and you'll have to pick him in the first round if you really want him.

Have the Cowboys learned their lesson? We may found out next year in April May.

In the next day or two, we'll look at the other position groups using the 2013 draft board. The 69% 'mis-graded' rate for O-linemen (outside of first-rounders) is the highest of any Cowboys position group in 2013. But which group do you think will come in second?

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