I have always been curious how this would work: Dropping the bottom teams in FBS in favor of the top teams in FCS, very similar to the way that European soccer leagues are run. In this, I am going to look at results from 2009 in a couple of different ways.System One: Win-Based
Bottom 5 of the FBS:Eastern Michigan (0-12)
Western Kentucky (0-12)
Miami (Not That Miami) (1-11)
Washington State (1-11)
New Mexico (1-11)
Top 5 (6) of the FCS:
Montana (14-0) - In Championship Game
Villanova (13-1) - In Championship Game
Richmond (11-2) - Lost to App State
Southern Illinois (11-2) - Lost to W&M
William&Mary (11-3) - Lost to Villanova
Appalachian State (11-3) Lost to Montana
Win by Montana would drop out S. Illinois, win by Villanova would drop out Richmond.System Two: Sagarin Rankings-Based
Bottom 5 Sagarin FBS (it is unlikely these will change):
Western Kentucky: 192
Eastern Michigan: 182
North Texas: 162
New Mexico State: 152
Miami (Not That Miami): 150
Top 5 Sagarin FCS (these might change next weekend):
Appalachian State: 75
So let's say we combined these two lists and dropped the bottom four out of the FBS, just for the sake of making promotion simple. EMU, W. Kentucky, Miami (Not That Miami), and NM State all appear on both lists, and would get bumped down to FCS. Montana, Villanova, William & Mary, and Appalachian State, the top four teams in the FCS playoff, would be brought up to replace. The teams would take opened spots in the most local conferences, replacing the bumped teams on the conference schedules.
William & Mary and Villanova would trade conferences with EMU and Miami, because of location. W. Kentucky would switch with App. State, again due to location, and Montana would switch with NM State.
If the FCS teams managed to win the next year, they would make the cut and get to stay. If they didn't, they would just get bumped back down into their old conferences. The old FBS teams would be required to make the final four in the FCS in order to move up again.
I feel like this would liven up competition in the FCS as well as lighting a fire under the bottom-rung teams in the FBS. Probably will never happen, but wouldn't it be an amazing change?