Robert Weintraub makes a good argument that the proliferation of the "cover-two" defense has reduced the value of cornerbacks. But there's no way they are less valuable than kickers and punters. The effectiveness of a kicker or punter depends in large part on the effectiveness of his teammates; if they have time to get the kick off, it's usually a good one. If their blockers allow defenders to interrupt them, then bad things happen.

Cornerbacks, on the other hand, are correctly described as living on an island. Their only direct support comes -- sometimes -- from a safety, and even in the case where a safety must tackle a receiver covered by a cornerback, that means the cornerback screwed up.

The value of good cornerbacks was well demonstrated in at least two games last weekend. In the New Orleans-Indianapolis game, one cornerback -- Jason David of New Orleans, formerly of Indianapolis -- made mistakes that led directly to 21 Indianapolis points! Conversely, in the Arizona-San Francisco game, both of Arizona's excellent wide receivers, Larry Fitzgerald and Anquan Boldin, were rendered nearly ineffective by San Francisco's defense. (Boldin caught a touchdown late in the game, but had only 22 yards receiving.) Thanks to the limits of televised football, viewers weren't able to watch how San Francisco's corners individually covered Fitzgerald and Boldin. But I have little doubt that San Francisco team executives felt pretty good on Tuesday about their big off-season free agent signing.

I absolutely agree with the above post. After glancing at interception, interception return yards, interception TDs, and forced fumble stats for the past 5 or so years, I believe it's hard to make such matter-of-fact statements about safeties being the most likely to force big plays like these. While the author may be correct (I didn't plow thru the numbers in a particularly analytical way), the gap between CBs and safeties on these stats (at the very least) is much closer than he indicates. Furthermore, DEs seem to be more likely to force fumbles than other positions.

Also, he argues that the parity of kickers in the league makes minor differences in the players all that much more important. He then uses the same basic idea to argue CBs are easily replaceable. The example of Indy replacing their corners does not illustrate this point well either. Indy had a 1st round draft pick and two 2nd rounders to replace their starters, and they likely based the decision to let the starters get away on these prior draft strategies.