(Kinda touched on that in the regulation/promotion thread) All the Non-NFL leagues would somehow have to converge together, so there's the "parent" league and a viable big minor league. Having as little dilution of talent as posssible, no separate CFL pillaging players, Arena League, World League, UFL, etc. Can forget CFL in lending support for that, Canada is protective of its heritage like SEC football is. But if there was a STABLE leage in the STATES without American players having to go to London and Barcelona and all that, Im sure the players would prefer THAT instead of playing for the Grey Cup. Then it'd have to cut into NCAA's players and operations too, cutting into their traditions and bankroll. While at the same time being fully compliant with what the NFL big trust wants COMPLEMENTING them instead of competing WITH them, before it gets bullied out of existence. After doing most of that before it even gets to the fan interest, yeah one could survive. Then its if we want to watch Kliff Kingsbury, Colt Brennan and those ol' Boise boys Jared Zabransky and Ian Johnson play on.
Everyone seems to think you have to win the NFL over... if you get them on your side, you're good. No pro or semi-pro league has been able to do that at a high-level. Why should new leagues strive to do that then? That doesn't work in business. Disruptive innovation is when you turn the "industry" on its ear and force the industry to adapt to you. That's the only way this could ever happen. Disruption. Not by playing by the NFL's rules. Not by catering to the behemoth whose revenue you want a piece of. You have to FORCE the NFL to support you by first hating you. You do that by becoming profitable and relevant WITHOUT their help. Then they'll listen. They you have leverage. No more old school mentality football leagues. If this gets done it needs to get done the right way, not the "old money" way. Cuban, if you read this and steal my momentum at least give me a cut.
The whole point is that between the NCAA and the NFL fighting against it, it will *never* happen unless one of the two of them are behind it or running it. So, it is my hope that the NFL realizes that a minor league system, owned and operated by it, could produce year-round profits for them. They like the NCAA because it is their cost-free farm system. But college football makes money... if the NFL wanted a piece of that pie... they could screw the NCAA hard and start their own system. It's just a matter of time before the market grows to the point it can sustain it.
I don't want to sound too negative but any professional spring football league will have a lot of competition against other sports especially during the NBA playoffs, NHL playoffs, MLB, MLS, etc. Also, the NFL Draft and spring college football scrimmages will get more viewers than some games of a pro football spring league.