The news that Diaz may be drawing interest for the job at Florida International is interesting. But it's likely to be more indicative of a collaboration between the Bellmont spin machine, a Florida International AD feeling out national candidates via media, and Diaz's use of media friendlies to raise a damaged profile, than a legitimate opportunity to hit reset at the defensive coordinator position in 2013.
Texas has done this before. When Texas fans grew weary of the Greg Davis act in 2007 - let's call it Greg Davis Souring Part III - Bellmont trumpeted media stories about Davis interviewing at SMU - a job he wasn't going to take and that SMU wasn't going to offer. Similarly, whenever Mack Brown heard criticisms of his offensive coordinator, he made cryptic references to the stampede of programs seeking to hire him as their head coach, including, amusingly the occasional vague NFL coordinator reference. Essentially, it was a ham-handed attempt to quiet the fan base by showing his desirability to others who appreciated him more.
Unfortunately for Iowa, Kirk Ferentz didn't get that memo.
As for Diaz, young, media savvy coaches often use the media as a means to lift their profile by attaching their names to coaching openings. After a year in which the Texas defense played at a historically poor level, Diaz may be eager to reclaim his reputation in the only place he can: the perceptions of the national media. They're far more receptive to buy into the narrative of a Texas defense destroyed by injuries, rather than malpractice.
The Florida International job isn't a very good one. Substandard facilities, awful support, an AD who is regarded as a bit of a unreliable snake. It would be a pay cut for Diaz (Mario Cristobal was making under 500K after all bonuses and incentives in his 6th year as head coach, Diaz currently makes 700K a year at Texas) and though taking a lower tier head coaching job is a common rite of passage for promising coordinators, Florida International isn't exactly Iowa State, San Diego State, or Cincinnati. There's lower tier...and then there's the lowest tier. Unless you're Bill Snyder, the very lowest tier tends to kill careers unless you can time your departure perfectly, buoyed by a Haley's Comet senior class.
But what if Mack is pushing him out?
Engineering your own soft landing, as Tuberville did fleeing Texas Tech, is always a reasonable possibility to explain this less than optimal career move, but that would have required Diaz to be called into Brown's office and told "I'll review your job status after the bowl game when I've had a chance to review the totality of the season. In the meanwhile, you really should look at some of these exciting head coaching opportunities out there right now." The message there would be clear enough: get that resume updated.
I'm doubtful that happened.
Mack Brown doesn't have the tools or mindset to sort through cause and effect in the 2012 Longhorn defense's performance and he has shown a propensity for believing rationales that favor comfort and continuity over change, particularly at this stage of his career. I suspect he's mad at Diaz, but I also suspect he's angry with all of his coaches, and that his ire is rooted mostly in self-pity. That's not a great place to analyze from. I suspect Brown's season narrative isn't much more complex than, "Our defense was bad while our offense was good, but then our defense got better while our offense got worse. And we got that youth. And injuries! So everyone needs to pick it up!"