Yeah I don't classify the late window as one of the 6 T1 slots that the mouse has. It's important, because its literally the only thing at that time, but its more T2 as it pulls numbers closer to an ESPN2 game, at best, and is mostly all centered on mountain/pacific viewers. That makes it kind of a separate deal. At the moment I don't expect to see the B12 in it often, but it may have a few BYU home games there, which may be why ESPN is less inclined to pay the Pac much. To your point, if they were to add a Colorado or Arizona, I do expect for it to be paid for with the after dark window, somewhat. With all those teams in mountain that means a 8:30pm kick off, as opposed to prime time if you're in pacific. The fact that this gets discussed as a positive for the Pac is more a negative than anything else. If all you have to offer is filling a spot that is barely watched, that's not really a crown jewel at the negotiating table.
ESPN paid a lot to gobble up the top B12 games (top four, best 6 out of 8, best 8 out of 12, and best 12 out of 20) and I think that was in response to the B1G deal becoming too expensive, so I'm pretty confident they're going to find a weekly window to show case them. It wouldn't shock me if they started getting a branded segment at noon after College Gameday or afternoon to go against one of the B1G marketing windows. The SEC will own primetime, outside some FSU/Miami/Clemson/ND road games.
At the end of the day, these are rough averages. I don't think it will be 3/3 each and every week. Some weeks will have a weaker schedule in one of the conferences and it will be made up by the others.
No i didn't forget, but its only 6 T1 windows. If the B1G signed with the mouse, the B12 wasn't getting slotted, they only have so much room. The Big Ten owned the noon slot on ESPN for a very long time and got great ratings, then they had another ABC game, usually primetime, each week and then some others scattered around the dial. The SEC and B12 took those slots.
As for Week 6, per above, not every week will be exactly 3/3 you'll see a flux. When the SEC plays all their cupcakes you'll see more B12, weeks like this you'll see more SEC its really season count we're looking at. It also will matter how everyone is doing. 16 teams with 9 conference games also means more loses. If Auburn or Aggy aren't world beaters, that game may drop. The River won't, due to rivalry game.