Of the 5 defensive coordinators, Nolan, Quinn, Zimmer, Eber and Parker, at least Quinn achieved a passrush and turnover type dee while his run dee sucked. But at least he accomplished 2 phases of the defense very successfully.
As far as the other 4 defensive coordinators, the defenses have all looked the same.
REGARDLESS of personnel.
Let me say that again, REGARDLESS of personnel.
So it's up to you to choose did every one of the coordinators suddenly totally suck at their jobs when hired at Dallas or just maybe the players were and ARE NOT as talented as projected?
The common denominator here is the players not their defensive coordinators.
Food for thought.