I've heard people speculate that the B12 doesn't want to span 3 time zones, but having games in the Mountain time zone could cut into the P12's west coast market share. Having games start at 7-8pm MT when teams like Texas and Oklahoma come to Provo could allow the B12 to compete directly with the P12 for viewership, rather than competing with the SEC, B10, and ACC in the Central and Eastern time zones.