But fat folks hog up other folks seating area anyway, so there is no gain in having more seating capacity if you can't even fit in the seat you bought, cause some fat joe is taking up his and half of those on both sides.
They should have a section with just bleacher seats for the uber-obese folks, so they can make each other miserable trying to squeeze in. I can see some blubber hanging out in the isles, with that move. It would require some gymnastic feats to get to the restroom, for sure.
But seriously, if chairback seats were put in, that would be at the expense of what, one seat per row? I can't see it being more than that. I think removing any armrests could give the added comfort/back support without giving up a lot of seating capacity.
Then adding essentially 4 mini-decks (put another jumbotron on the other side and place the decks in between the monitors and the press boxes), could get the capacity back to 110,000 easily. And it would be the best college stadium in the country (size/capacity, comfort and amenities).
I thought I read some comments from Mike Hamilton about them exploring some options in the future, that sounded to me like this was one of them. Not sure. There are plenty of 3 deck stadiums in the pro's, so it wouldn't take an engineering marvel to pull it off.