You can argue numbers/years but with the emphasis on good QB play in the NFL, the prospect of starting over is not too enticing.
If they were to go their separate ways, what's Dallas suppose to do? Go after Cutler? He's apparently now the biggest name in the 2014 FA market for the position. Besides, throwing the lack of playoff success away (i know…), he's a top 10 QB, no? If you get one of those guys, you have to do whatever you can to keep them.
Now, hopefully Uncle Jerrah doesn't smarten up with the OL/defense.