Because this is real life and not madden










The correct answer is fatigue. Your lineman need a break, you defense needs a break, etc..
You need depth for that and sadly most teams don't have that.It's able to work to a certain degree because you're able to dress many more players for a college game

It reminds me to never take these cats seriously.
Because this is real life and not madden

eagles do and chip has 20 wins in 2 seasons with a "gimmick offense that everybody will figure out now that they have tape on it" with nick foles and mark sanchez as the quarterbacks.
chip knows it will wear down the defense hence all them shakes and monitoring players sleep and all that. you just need 1) an accurate qb so you dont miss the easy throws and 2) not have cary williams and brad fletcher as your starting cornerbacks
once you are up 14-17 it makes it easier for the defense anyway because you know the other team is going to have to throw to catch up so you can just rush the qb the rest of the day and not worry about the run as much