Geography, another of the key factors, really boils down to money, too.
First, athletic directors like Guenther say they'd like any addition to be contiguous with the current Big Ten or close to it.
Talking about Texas, Guenther foresees big, expensive travel headaches for sports like soccer and volleyball that already can't cover their costs.
"You'd have to really restructure the way you're currently competing," he said.
The second piece of the geographic consideration is television: Expansion makes more sense if it turns big TV markets like New York or Texas' big cities into Big Ten markets, both for the Big Ten Network and CBS, ESPN and ABC.
Penn State, according to University of Chicago economist Allen Sanderson, hasn't delivered as much of the East Coast TV audience as the Big Ten would have liked.
"For New Yorkers, they think Penn State is somewhere right around California," he said.
Few of the schools mentioned as potential Big Ten targets have said anything publicly about the possibility. Notre Dame insists it isn't interested and Longhorns AD DeLoss Dodds told The AP this week that Texas hasn't been approached by the Big Ten — in spite of media reports to the contrary — and is happy in the Big 12.
Alvarez said recently that Big Ten commissioner Jim Delany could make a recommendation to conference presidents on expansion as soon as this summer. When a decision is made, Carter thinks the Big Ten will expand.
"The allure of being able to extend the footprint of the conference and the potential to generate sizable incremental revenue," he said, "makes all the sense of the world."
Ikenberry disagrees. He was a key figure in bringing Penn State on board.
Speaking in the same campus office he occupied when the Nittany Lions joined almost two decades ago, he says that, in addition to protecting their revenue stream, universities have something else to guard.
"There's a lot of tradition and, as the Big Ten changes, that tradition gets tweaked over time," he said.
"Wise heads at the end of the day may conclude that, yes, there are a number of theoretical options out there for possible new members of the conference, but, at the end of the day, the Big Ten tradition is better preserved with the status quo."
CFT: Johnny Manziel nearly transferred out of Texas A&M before the 2012 season after being suspended, according to reports, but he stayed after his successful appeal.
About 325 former Penn State players, among them Kerry Collins and Paul Posluszny, have signed a statement supporting the lawsuit filed by the family of former coach Joe Paterno.
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