Sure a Purdue can still upset an Ohio State, but it doesn't matter anymore. So that's where it hits me. I distinctly remember playing touch football in my backyard, and my dad yelling to us that Indiana was tied with Ohio State. We stopped the game, and watched it, due to the implications. We've removed a good deal of those implications. If Indiana beats OSU, OSU can still beat UM and PSU, reach the CCG, where they will likely win, and go to the CFP.
There is something here that I want to expand upon. IIRC, you grew up in Michigan as a Michigan Fan and in a Michigan fan household so when Indiana was tied with Ohio State, that didn't involve your team. My guess is that your childhood touch football game in Michigan was with a bunch of Michigan fans with *MAYBE* an MSU or ND fan or two sprinkled in so NOBODY involved in this story was a fan of either Indiana or Ohio State. Despite that, you dropped your game and ran inside to watch the IU/tOSU game because it was a REALLY big deal. The potential of Ohio State losing to Indiana was HUGE because it would rearrange not only the league title picture but the national title picture as well.
This is where expanding the playoff to two (BCS) then four (current) and soon 12 is necessarily detrimental to the regular season. If a bunch of kids in Michigan are playing touch football next year and Indiana is tied with Ohio State why would they care? Their teams aren't involved and even if Ohio State loses to Indiana that only marginally decreases their chances to win the league and the NC.
For me, just flipping channels I've done a similar thing. In the past when any highly ranked team from any league was in a close game, I'd flip to it because it was important.
The top two teams this year have such ridiculous schedules that it is unlikely but lets say that Georgia or Michigan has a crappy game and their opponent plays out-of-their-minds and the Dawgs or Wolverines end up in a dogfight late in the fourth quarter with Ball State or Bowling Green. In the old days that would have been monumentally important because a loss like that would more-or-less have eliminated them from the NC race. Every fan in the country would have, per your example, dropped their touch football game and run inside to see if the Cardinals/Falcons could pull off the upset. Now, who cares? Even after losing to BallSt/BGSU, the Dawgs/Wolverines would still absolutely control their own NC destiny. Win out, win the SECCG/B1GGC, and you are absolutely in even the 4-team CFP despite an embarrassingly ugly upset loss to BallSt/BGSU.