Following the Cowboys 8-8 season, Jerry Jones went on the warpath, promising to "make things uncomfortable" around Valley Ranch.
No kidding.
So far, the defensive co-ordinator Rob Ryan has been fired, and replaced by Monte Kiffin, who, it is rumored, is going to install the Tampa 2 defensive scheme.
The special teams coach Joe De Camillis has just left for another team.
Now, it seems that Jerry wants a dedicated offensive co-ordinator, and, not surprisingly, Jason Garrett does not, or if one is installed, he wants one without head coaching experience.
This is not going to end well. At this point in time, Jason Garrett has been converted to a lame duck, a hand-picked proxy for Jerry Jones. Whoever is installed as offensive co-ordinator, everybody in the club will know that Jerry is really the head coach, and, if push comes to shove, they will call Jerry to ask what is happening. This is a replay of the period of time when Dave Campo and Chan Gailey were the head coaches.
Not all of this is Jerry's fault. Jason Garrett has been stashing family members on the coaching staff, which is not a good idea. Nepotism is never attractive in action. By doing so, he has left himself vulnerable to criticism and unrest within the coaching staff. Of course, he could argue that he is merely following the example of his owner, whose son is also working with the Cowboys as the de facto head of player personnel...but then his owner is the one paying the bills, so he gets to make the rules.
One role that also needs to be filled is that of a game management specialist. The Cowboys, to use Gregg Easterbrook's words, have low football IQ. They consistently get confused in game situations, waste time, burn timeouts, and lose opportunities to advance. This has to be fixed.
UPDATE - With the departure of John Garrett to the Tampa Bay Buccaneers, Jason Garrett's position becomes more tenuous. I am starting to wonder if Jerry Jones already has an option deal with another Head Coach, and he is simply trying to force Jason Garrett to resign, in order to avoid paying off his contract. Logically, either John Garrett has decided that his brother is on thin ice, and is getting out ahead, or has been told by his brother to go somewhere else for his own good.
UPDATE 2 - This article from Rick Gosselin does a good job of explaining why these changes have occurred. The money quote is this one from the Q&A:

Q. It didn't seem like coaching was as big an issue this season as a lack of talent. Why then are we seeing wholesale changes to the coaching staff but not changes in the scounting department and front office?
A. Jerry Jones is fond of both his general manager (Jerry Jones) and his director of player personnel (Stephen Jones). So any changes need to come from the other side of the building from the coaches and players.

Troy Aikman is also unimpressed by the changes.
Hell, I am unimpressed by the changes. They destroy continuity on all three areas of the team. History shows that the most successful NFL teams are those with continuity in coaching. The Cowboys are on a road to nowhere in terms of results with this level and frequency of change. I just hope that the Cowboys are as aggressive on players as they have been on coaches. At least that would confirm that the changes will impact everybody, not just the coaching staff.