Yah........not sure I would do that one. I would be very tempted, however. I would definitely give up a 3rd, probably a 2nd round pick. Draft picks are too important. And he would have to sign for 6 million per year or less.
With Adrian Peterson and this line, Cowboys might have the first 3000 yard rusher in NFL history.
They'll only sign chris johnson if none of the 4 RBs they already have fail in camp. Highly unlikely though the way this OL will be opening holes.