Wrong. Those teams can pull in a ton of coin (maybe not equal, but still a ton) without having to play the top 10 teams every year.
There are more than 16 programs in the country that are sustainable without being in your hypothetical conference (teams like Oklahoma State, Virginia Tech, Arkansas, Tennessee etc). IMO, those "second tier" teams would benefit most, because the road to 12-0 would be incredibly easier, considering they wouldn't have to play LSU, Alabama, Texas etc.
16 of the best teams in the country would have to be absolutely suicidal to agree to play each other every single year.
If you believe for a second that Top ___ rankings, BCS slots or mythical national championships are going to drive these decisions then you simply don't have a clue. It's all about maximizing revenue and we know that in college athletics the money is in football. Football, and specifically the right to broadcast football games and the revenue derived therefrom, will drive what eventually happens. It may take a bit but there are clear tranches out there and the cream will self-separate from the rest soon enough.
Consider the present Big XII: this fall the Big XII will play five conference football games per weekend. Of those only one game each weekend will feature a team whose mascot is a cow and that game will have a value, in terms of national audience and sales of advertising slots therein, probably on average greater than (or at the very least quite similar to) the sum of the values of the weekend's other four conference games combined.
Now consider a hypothetical Super Conference (play with the names as much as you like) comprised of: Texas, Notre Dame, Penn St., Ohio St., Michigan, Florida, Alabama and USC. Each of those teams brings a value not perhaps equivalent to Texas but somewhere in the ballpark. Thus every game of the regular season is nationally prominent in precisely the same way that a UT Big XII game is only no one ever has to watch these teams beat up on the little sisters of the poor any more. The value of broadcast rights for this conference is probably 3-5x the value of any present conference and likely more since every game will feature a valuable property on both sides of the field rather that just one as is the case in most conference games now. And you really believe that wouldn't induce teams to want to join?
Competitiveness isn't really an issue. Form the Super Conference with 8 teams, play 7 league games & schedule 5 OOC wins. Or form with 12, play in 3 or 4 team pods and schedule 5 or 6 OOC wins. Similarly a 16 team conference comprised of 4 pods of 4 teams each leaves room for 6 scheduled OOC wins. There are plenty of ways to arrange such a conference without making the conference slate a Bataan Death March.
BCS? Please. A 12 or 16 team conference arranged in pods could conduct a 4-team conference championship playoff whose revenues would probably exceed those of the present BCS bowls. Or imagine a 16 team Super Conference featuring your pick of college football's 16 biggest names and further imagine those names not being part of the BCS picture. What would the BCS be worth in that case? Certainly a fraction of its present value. So there would be great incentive on the part of the BCS to include as many Super Conference Teams as was feasible; certainly one and probably a couple guaranteed. Perhaps the hypothetical Super 16 would bypass the BCS completely and invite the champions of the remainder of the SEC, Big XII, Pac 12 & Big 10 to compete in an 8-team playoff against its four pod champions and award its own National Championship. Again, that arrangement would dwarf the present system financially.
They money is simply too much to ignore and there are several conferences that have grown well beyond regional and local rivalries already. The next clear step is a national conference comprised of only the most valuable franchises. It may not happen this year or next but it is going to happen.
