In addition, as everyone told me time and again, the Rangers TV deal ran out in 4 years. Combine that with the Mavs TV deal running out just a few years later and it could either form a foundation for a new sports network, or preferably cause Fox to pay an ungodly amount of money to keep the teams on FSN. Fox had more to lose from a competitive sports network being formed, particularly in Texas, than a new network had to gain from being created. So the leverage of owning both teams was enormous.
That was a financial win for both teams. The ability to earn more money from TV revenues for both teams meant more money could be put on the field/court. It was a unique situation.
Honestly, I'd like to see Cuban buy the Pittsburgh Pirates. He has shown an interest in buying them, and I actually think he could turn them around.