If they add only one school in the Big Sky, it will be NDSU. They have a big supporter in the Montana State President, and to my knowledge, SDSU has no booster in the BSC like that. Also, the obvious travel partner for Northern Colorado is NDSU. Have you checked the flight schedules to see how easy it is to get from Denver to Fargo? An hour and a half flight and you are on campus or at your hotel 10 minutes after landing. You would have to fly into Sioux Falls and bus to Brookings. That is something that NDSU has over SDSU or UND that the other schools in the BSC will look at, especially with Delta starting flights from Fargo to Salt Lake. Every Big Sky school has to fly into Minneapolis to get to Grand Forks in every sport except football (where they would probably fly on a charter). The BSC will not take SDSU because it thinks it will have an easier time adding NDSU & UND in the future. You may want to think UND has that kind of appeal, but I'm afraid you are mistaken. They will take the one they consider the best option to get out of their scheduling nightmare a nine team league has caused them. They know going to a twelve team 2-division conference will take some convincing of some of the presidents (maybe 2 or 3 years down the road), but they really want an even number for scheduling, so adding one is their immediate option.