This was my major concern from the beginning. Everyone knew the DC's would do their best to shutdown the run, the Cowboys only hope was to make them pay and back off so they could run the offense.
The QB isn't great and he doesn't have great receivers and the OL is no longer great. The HC and OC never were great. This could turn into a great big mess quickly.
The team's success was based on a top OL, so that Dak could be conservative and not have to win games on his own, due to his inexperience.
But with no Frederick, no Leary or experienced replacement for Leary, the line isn't a top OL.
Add to that no Witten as a security blanket for Dak, to get some first downs, and having to get in sync with 3 new receivers in Hurns, Gallup and Thomson, he's being forced into being a Peyton Manning or Aaron Rodgers, and he's just not at that level (if he ever can be, or be close to it).
But remember the Eagles "Dream Team" of a couple of years ago? Great plan, but it failed miserably.
The Cowboys' plan of a return to the 90's, with Aikman throwing only 18 tds a year, and Emmitt winning rushing titles, has failed. Can't really say it was a bad plan, if Frederick was still on the line, and if Leary could have stayed, I think it might have been much better.
As the old saying goes "the best laid plans of mice and men..."