Jason Wilde spoke with the Green Bay Packers special teams coach about Randall Cobb, and Shawn Slocum said that Cobb will remain in his role as a kick returner "no matter how vital he becomes on offense." Of course he should. The alternative, sitting an outstanding kick returner so he's ready to play as the No. 4 WR, is a ridiculous waste.
The Packers's special teams unit has been a sore spot for many seasons, but they finally played well in 2011 and earned a No. 8 overall ranking from Football Outsiders. Mason Crosby had a good season too, but the Packers scored a 3.1 and 3.8 on kick returns and punt returns, respectively. Those numbers were a dismal -6.1 and -2.4 in 2010. That's a hidden part of the game that helps explain, in part, why the Packers went from 10-6 in 2010 to 15-1 in 2011 while their defense was swirling the bowl.
Cobb's good enough to start at receiver in the NFL, but the Packers have the luxury of not needing him to. And as a late 2nd round pick, it's not like his salary is a drag on their salary cap, or on their ability to acquire help at other positions.
As a side topic, I haven't understood the rumors of trading James Jones. Those rumors were started once it was made known that Donald Driver was coming back next season, and his trade could also give Cobb more playing time. But Jones is more valuable to the Packers than to any other team. According to Football Outsiders, Jones was the No. 18 WR overall in 2011, and he wouldn't be that good on any other team as a No. 1 or No. 2 WR. That's the equivalent of Vincent Jackson's production, but at the price of a No. 3 WR. Unless another team wanted to give a high draft choice in return, and he's not worth that much on his own, the Packers wouldn't receive equal value in return.