When TCU got invited to the Big XII, most followers of conference expansion news were shocked. And for good reason. There are a plethora of reasons why TCU is not a good pick for the conference:
First and foremost, TCU is a small school with low attendance and a small national fan base. According to this oft-cited NY Times study, TCU boasts a whopping 370K fans nation-wide. They only average 42K in football attendance. Both of these figures are just barely more than Big 12 bottom-dweller Baylor. Of course, these numbers will likely increase with BCS membership, but one wonders why the Big XII would jump for a team that adds very little revenue to the pot (a pot that is now going to be evenly distributed).
Additionally, adding another Texas school is unlikely to bring more television viewers to the Big XII. Even if TCU's following were on par with other schools in the conference, Frogs fans likely already follow Big XII football (Texans are almost honor-bound to watch the Longhorns). Just like BYU fans watch most Utah games, most TCU fans are already watching Texas games.
Finally, TCU does nothing to repair the Big XII's image of instability. The Frogs are entering their fourth conference in the last decade, and they didn't even play a single game before ditching the Big East. If the Big XII isn't able to fix itself and another BCS conference offers TCU a spot, it would surprise no one if they bolt again.
The only logical reason for bringing in TCU is that they were the only team willing to enter the sinking ship with few or no conditions. As noted, the Horned Frogs are college football's conference-hopping (no pun intended) team, so the Big XII knew that TCU would jump (ok, pun intended) at the chance to play with the big boys, especially given the recent collapse of the Big East.
My guess is that the top teams on the Big XII's list (BYU, West Virginia, Louisville, and Cincinnati) were not willing to sign on without assurances that the Big XII would not bleed out and die in the next few years. TCU, on the other hand, has shown a propensity to join any conference that offers a (seemingly) brighter horizon. So, the Big XII invited them in order to project stability in hopes to attract other the teams higher up on their list.
Whether BYU is still on that list is up for debate. And only time will tell whether the addition of the Horned Frogs is enough to lure any other team to the fold. It's hard to believe that the Big 12 thinks that TCU alone is enough to make up for the loss of Nebraska, Colorado, Texas A&M, and possibly Missouri, so my guess is that they want to add at least one more team.
In the end, TCU does not stabilize the Big XII. In fact, it seems to make the conference (and the Horned Frogs) look desperate. As this drama continues to unfold, Cougar fans will be anxiously waiting to see if the Big XII will make the necessary concessions to get BYU on board.