Yes, but Dallas lost a good deal of these players at once. If you look at the 1992 and 1993 Cowboys, what got Dallas to two super bowl wins? 1) a good line and 2) good running game.
Dallas has not had a consistent running game for ages. It started to develop but it fell apart due to injuries.
Dallas started to put things together on Thanksgiving, but then lost Marion Barber. Had Dallas won in Pittsburgh and at home against the Ravens, Dallas would be going to Arizona Saturday.
I also think had Jerry let Pacman loose when he should have, the Cowboys would have made the playoffs, he poisoned that lockerroom. All you had to do was hear Greg Ellis and Zach Thomas boasting that they are free agents, and want to get the Hell out of Dallas, should tell you what a bad atmosphere it became.
Contrast that with the Dallas Stars who cut loose Sean Avery, and have played well ever since.