I think the biggest problem was not the switch to the 4-3 but the hiring of a dinosaur to run it
I think that was two mistakes. It was completely idiotic to switch back to the 4-3. The defense of it was probably the most illogical you could ever come across. To think you build a defensive philosophy on the remote chance that you suffer a rash of injuries that would otherwise cripple any defense. But not this one. Street free agents can walk in and play it. Of course at a street free agent level, but hey.
All things equal, I'll take a 3-4 defense over a 4-3. Considering we were already entrenched in that scheme, it made no sense to make the switch. It was merely the scenery change the owner used to distract the fans one more year. Rob was the scapegoat. He's belly laughing right now in New Orleans.
Kiffin might have been a great coordinator at one time, he had great players whenever he was productive, but he's at an age now where I'm not sure why you would even expect him to thrive. It was just such an odd hire when you're trying to win something while Romo, Witten and Ware still have something left. The clock's ticking. It's now or never with this group. Let's completely revamp our defense and bring in a 70 year old who hasn't coaching in the league in years to run it.