"UTD and UTA hate each other"
Legend, if this was ever true ("hate" is a strong term...maybe "distrust"), it has gone away over the last decade. UTA and UTD are so intertwined anymore. There are so many collaborations and partnerships between the two universities; they are really helping each other. The universities are close at the presidential, dean, an professor levels. Students are in joint degree program at both universities. Doing research together on both campuses (and at UT Southwestern) and forming joint degrees that either university alone would have trouble getting in today's environment. For instance, as brand new examples, UTD is currently latching-on to UTA for a joint Ph.D. in mechanical engineering, and UTA is getting a new Ph.D. in geology from going-in jointly with an already existing Ph.D at UTD. Both universities are also working very, very closely with UT Southwestern. UTA even has its own labs at Southwestern.
I think UTA does have some limited collaborations with UNT Denton, but not nearly so extensive as with UTD. (Digitizing the maps in UTA's special collections comes to mind.) UTA probably works more closely, in research terms, with the UNT Health Science Center...I know there is stuff going on there. Being in the same system makes a lot of collaborations easier and logical.
Anyway, UTA and UTD certainly do not hate each other. Quite the contrary, the two universities have never been closer.
This is interesting about the Union project getting shot-down by the Coordinating Board. (The large majority of projects are approved.) UNT will go back with a new proposal. It is likely that the project will need to be scaled-back, or, at the least, other sources of funding will need to take the place of some of the student fee commitment. I was shocked by the $137 million price tag, to be born almost exclusively by student fees, and I think the Coordinating Board was, too, esp. in the current environment. The chancellor and president were not tuned-in to the political (and fiscal) climate.