Caveat Emptor: Free Agency Lessons The Cowboys Should Learn From

Every year, hundreds of free agents become available at the start of the league year, and an immediate free agency frenzy sets in as the biggest names go to the highest bidder, often within hours of the start of the new league year.

There is one defining characteristic that every one of these free agents shares: their old team did not want to re-sign them, at least not for the price the player is demanding. That in itself should make every acquiring team wary of the free agents on offer. Hence "caveat emptor" or "buyer beware".

There are a couple of common free agency mistakes the Cowboys should be particularly wary of in 2013:

1. The defensive end coming off a big year

We covered that in detail in yesterday's post on Anthony Spencer: We know that historically, pass rushers coming off a big year in terms of sacks tend to regress to the mean in the following year. Anthony Spencer for example had his statistically best year with 11 sacks last year. It is unlikely that he will repeat that number in 2013, but some team probably not based in Dallas will pay him based on the assumption that he will repeat those sack totals not just in 2013, but in 2014 and 2015 as well.

The Cowboys will have to shell out big money for a DE either way. If they let Spencer walk, they'll have to go after a suitable replacement, who probably won't come a lot cheaper than Spencer anyway.

If the Cowboys are going to invest in a free agent DE, they need to follow the approach they took with Brandon Carr: sign a player young enough and with enough upside to provide three-plus years of future high-level performance. In this year's free agent class, Michael Bennett (TB, 27), Michael Johnson (CIN, 26), William Hayes (STL, 27), Paul Kruger (BLT, 26) and Cliff Avril (DET, 26) fit that bill, but all of them are likely going to be hideously expensive.

2. The veteran running back

The Cowboys will likely draft a running back in April, but could also bring in a veteran running back as extra insurance. But spending big money on a veteran free agent running back is not exactly the sign of a forward-thinking organization. This is a lesson the Cowboys had to learn the hard way when they made Marion Barber one of the highest paid running backs in the league in 2008, only to release him two years later and take a huge cap hit in the process.

But that mistake is not unique to the Cowboys. In fact, it happens every year in the NFL. The table below features the top seven free agent running backs who changed teams in 2012, and how their production changed from 2011 to 2012.

Only two of the seven backs managed to improve on their 2011 performance after signing elsewhere. Granted, these are not the type of megamillion contracts you often see in free agency, and I haven't done this exercise for previous years, but I'm fairly certain the results would look similar for both for previous years and bigger contracts. There are not a lot of running backs in the league that get better with age, and those that do, or those that are able to maintain a high performance over a long time, hardly ever hit free agency.

3. The second/third wide receiver in an effective passing offense

This is a situation where the performance of a receiver is based more on the offense he's playing in than on his talent. In 2007, the Lions were the 9th ranked passing offense in the league. The leading receiver on the team was Shaun McDonald and a rookie wide receiver named Calvin Johnson was looking to relegate the previous year's number one wide receiver, one Roy E. Williams, into third place on the depth chart. The Cowboys decided to sign Williams, the second/third receiver in an effective passing offense, in what turned out to be a pretty bad idea.

The situation reversed last year, when Laurent Robinson emerged in Dallas as a strong second/third wide receiver in the Cowboys' pass-heavy offense. With 11 TDs and 858 receiving yards to his name, Robinson signed a five-year, $32.5 million contract in Jacksonville, but only managed 252 receiving yards without a TD in an injury-marred and possibly career-ending season in Jacksonville.

If the Cowboys are looking for a veteran wide receiver, their best bet would be to sign a good receiver playing in a bad offense.

4. The veteran defender from a top defense

There's a piece of NFL draft wisdom that teams disregard at their own peril: "Never trade with New England. They win every time. When the Patriots call, you hang up the phone."

The free agency equivalent is to never sign a veteran defender from a top defense. The Ravens, Steelers, Patriots and Bears have consistently ranked among the top defenses in the league over the past few years. In a similar rationale to the point about the second/third wide receiver, the issue here is that you're never sure whether the player you're acquiring is good because of his talent or because of the scheme his team employed.

Team success often obscures the view of individual performance. Nowhere is this more evident than when a run-of the-mill QB wins a Super Bowl and is suddenly declared elite on the strength of three or four games, while the previous 80+ regular season games are conveniently swept under the rug.

And the same holds true for a veteran defender from a high-caliber defense: Make sure you're buying a top quality product, not a brand name product with questionable ingredients.

5. You are going to overpay regardless

Even if you heed the four previous points, you'll end up overpaying for your free agents anyway. In fact, teams should consider themselves really lucky if they get a free agent that meets their expectations. Brian Burke from Advanced NFL Stats explains why:

The team that most grossly overestimates a free agent's value will very likely be the team that offers the most and wins the auction. The upshot is that free agents tend to be signed by the teams that erred the most in predicting their true worth. That's why free agent signings turn out so disappointing so often.

There are only very few exceptions to this point. One of them is that the free agent may actually be more valuable to the new team than to the old team. Martellus Bennet is a recent case in point here: Maybe the new scheme or system is a better fit for the player; maybe the player steps out of the shadow of an elite and/or high-cost player; maybe the coaching staff on the new team can help the player improve more (this of course is a common fantasy among all NFL coaching staffs). Lots of maybe's and a lot of wishful thinking going on here.

At the end of the day, you'll have to approach free agency with realistic expectations. It's a very costly process that's designed to plug holes in your roster. Don't ever think that you're just one or two players away, because no team ever is, especially not in this era of the NFL.

And once you understand that, you'll also understand that the best way to assemble elite talent is through the draft, and you never, ever trade away your premium draft picks for veteran players. Instead, you should trade away your veteran players for premium draft picks.