There are only two programs in the Big Ten that are all but guaranteed to be successful across long stretches of history. Ohio State and Michigan. Facilities, income, alum and booster programs and established winning traditions are more than likely to keep that in place. Two more programs, Penn State and Nebraska would seem to be capable of joining the top rung of the conference. Wisconsin, Michigan State, Iowa and Minnesota -as others here have noted- will go up and down.
Last game of the year does not make The Game special. It's the long term quality of the two teams. You can't set up a schedule that eliminates the possibility of two teams having to play each other twice, or even twice in a row, in a CCG set up. But you can look at the long term records of all the teams and realize that Ohio State and Michigan have the most likely chance of being the two best teams in the conference. Putting them in the same division guarantees that the CCG will frequently not be a true CCG.
Of course you can. It's incredibly short sighted and backwards to sacrifice the stakes of singular, annual clashes with Michigan (or Michigan State lately) just to posture for the infrequent hypothetical matchup in the CCG.
Predicting football programs is a very tricky business. Sacrificing great annual matchups to inflate hypothetical CCGs is trading known greatness for infrequent matchups that may rarely or never happen.
Harbaugh should restore them to a powerhouse but we can't bet on that, especially since the NFL will come calling if he does.
Remember how easy Michigan supposedly had it when they were put in the opposite division from OSU? How many CCGs did they make?
Remember how many times Michigan failed to play good let alone league title contending football in the past decade?
Remember how every single person on the planet was dead wrong about how Wisconsin OSU would play out in the CCG?
Who says UM in a CCG will be any better than playing Wisconsin, Nebraska or whomever they add via expansion? Especially if they reduce the stakes and challenge our sanity by playing "The Game" twice?
Right now, UM stands in OSU's way every year, and despite being historically awful, they've given OSU a dogfight most years. 14, 13, 11 (loss), 09 were not pretty for OSU. 12, 08 & 07 were a lot closer than they should have been for awhile. Now they have a good to great coach and new life. I'm not remotely interested in posturing for a postseason rematch (let alone the unthinkable, not playing in the regular season) in order to gamble on a postseason-averse program making a postseason matchup supposedly better.
Thankfully sparty switched back to this division so they can be another annual great game. Sparty may take a step back this fall but still provide a great challenge for OSU as a regular season opponent. That same record might not buy them a trip to Indy.
Sparty won in 2011 and nearly ruined 2012. OSU skipped them in 2013 and made the CCG as a result (where they lost to them). Again Sparty was the playoff gatekeeper in 2014 and they should remain that in 2015.