Agreed. But out of conference opponents have been scheduled going out two or three years, and since the Big 12 plans on replacing both A&M and Mizzou with new conference members then Kansas will be playing TCU or West Virginia on the last Saturday of the season. So Mizzou will have to find someone else to play. And after a two or three year hiatus the Border War will be dead anyway and Missouri will have killed it. Simple as that.
If UTx or KU desire, they can certainly buy out one of their out of conference nobodies and play aTm or UMo, respectively, if they desire. Also I bet that for example UWVa or TCU would be happy to schedule it so they could play Pitt and SMU, respectively, that last weekend too.
I know that highly desired at University of Northern Illinois game is tough to give up for 2012, but I bet there is a buyout in the contract. So if KU want to play UMo, they can easily do so.