The defense has to get upgraded, but we still need to stick with what worked last season. It is not a coincidence he had perhaps his most well rounded and efficient season ever.
The offense was so difficult to defend last year because of the balance it had. More precisely, the offense put defenses in the catch-22 of them coming up to play the run and Romo throwing over the top of them, or them backing off to stop Romo and Murray running through the big gaps that creates.
The Cowboys looked at that and decided that the difficult portion of that equation is finding a passing game that can back defenses off enough to allow the very good OL to do what it needs to in order to open up running lanes. Not to find a RB who can run through the gaps created by the strain of having to defend both.
One need look no further than the Arizona game last year to find evidence of the synergy created by putting a strain on a defense with a very good passing game coupled with a very good running game. Or should I say the lack of synergy in that game.
Arizona had correctly deduced that with Romo out, they could bring up whatever they needed to in order to stop Murray and the run game. They filled the box with bodies and sent run blitzes all day. Weeden was incapable of making the Cardinals defense pay for that, and so the day was lost for the Cowboys.
The running game simply wasn't effective at all. That great OL and Murray were stymied the whole game. Murray didn't magically get the yards or fall forward enough to put the team in short yardage situations that they could easily convert. There simply was no running room.
The defense wasn't caught in a situation where it had to guess what was coming. They couldn't really be burned for selling out to stop the run. It was an easy day for the Arizona defensive coaches.
The following week, Romo was back and so then, was the running game.
The coaches had a commitment to the run game and an OL to pull it off. That added to the passing game that Romo and the receivers have always provided, made the Dallas defense all but impossible to defend.
Just look at the losses from last year:
SF - Romo just wasn't right for the SF game to open the season. His back and the recovery from that surgery had him off kilter in game 1. I don't think SF wins that game without the turnovers provided to them.
Was - Romo got hurt midway through that game. Would Dallas have won if he didn't get hurt? Probably. They almost won even with the injury. Romo shouldn't have come back in as he just wasn't himself.
Arizona - I have already addressed this loss above.
Philly - The whole team seemed off with almost no rest or time to game plan for the Eagles. Romo did seem off but I think this is likely a game Dallas loses no matter how you play it. They just weren't right that day. It happens.
So, of the 4 losses last year, three of them were because Romo either wasn't right physically, or he didn't play at all.
In all but one game last year, the catch-22 that defenses were put in (or not put in) had a huge impact on the outcome.
What I'm getting at here is that it wasn't Murray that put defenses in that no-win situation. It was Romo and the passing game that forced teams to drop back to defend the pass. When defensive coordinators did that (and they had to in order to have a chance), then the OL and Murray would make them pay.
The Dallas coaches know it was the running game making defenses pay for stopping Tony that made the offense so difficult to defend. They aren't about to not do the same thing this year too. They saw the opportunities Murray had last year because of the potent passing game, and they understand that as long as Romo and the receivers are creating the problems they do down the field, defenses will have to stop it. When they do, the running game will find room to run and there then, will be the catch-22 that we all loves so much last year.
The coaches understand that what Murray did last year was, in large part, a function of the position he was put in by the passing game and the very good OL. They correctly (IMO) decided that what Murray gave them wasn't worth $8M per year and that the running backs they have can do an awful lot of what Murray did last year.
I think they realized that Romo and the passing game is what they can't lose. That with that functioning at a high level, along with their OL, will allow many RB's to play at a high level.
So, that is my long winded way of saying that, going forward, I don't think you have to worry about the team forgetting about the run game. They saw it just like we did, and they know, just like we do that it was almost impossible to stop.