In theory, if Romo said that this was his last year, and pointed out that he sat down and didnt say a word while Dak went one and done, there isn't any real reason why the role couldn't reverse for one year. The argument that it would hurt Dak's progress is stupid, Tony didn't play at all for 3 1/2 seasons and Aaron Rodgers didn't play at all for 3 seasons. The only people who wouldn't like it are the Dak slobberers.
In reality, I still think Tony would voluntarily step aside even if Jerry said he could get the job back. I think he remembers when he was Dak, and how he got the job himself way back when. And I think he respects that.