Hold up!
I just hate it when I am forced to defend the Jones's. There is enough to criticize without sports Jounalists misrepresenting the math and distorting the truth.
By contract, all teams must pay their players a specific percentage of the league's total revenue. If any of that money is not paid out then it is automatically rolled over to the next season.
The Jones's never made any secret of the fact that they were trying to rollover cap money in anticipation of future large contracts. This season, they rolled over almost 5 million dollars.
Every unanticipated increase in their total salaries means less money to roll over for the future. For example, Zack Matin's contract forced a reduction last season. Fair enough, good investment.
Any time the Cowboys must add a new "outside" player to the roster, like Jason Peters, the result is further reduction of that rollover amount.
Still, in the end, every team is going to be about equal. This is part of the NFL's bargaining agreement with the NFLPA.