I was just simming a game and watching, and one team got up big 30-3 by the end of the first half, and the playcalling logic thereafter did not at all resemble a realistic set of results.

1) The team behind 30-3, but still with a whole half of football, kicked a field goal instead of going for it on 4th and 3 from the 3 yard line.
2) The team down 30-3 was still running the ball
3) Too many runs on 3rd and long in general
4) Not sure but I believe no onsides kicks were attempted

We used to have it where teams would go for it more, go for onsides kicks, throw the ball constantly, etc. to try and get back into the game, but it normally ended up in a bunch of turnovers, short fields, and scores in the 90's and 100's for the other team. So at a certain point if they get down that big they tend to get conservative just to get through the game. It's always something we're tweaking between versions though.

Maybe you can allow the player to choose how they want to proceed in certain situations... say, give a % of how often to go for it on 4th down, rather than letting the AI choose. The more input the player gets as far as play calls during a game, the better, in my opinion.

Teams throwing constantly and going for 4th down conversions are easier to defense. In real life you can scheme against that offensive logic much easier than if they remain balanced and try to create match up issues isolating DBs and LBs on WRs and backs.

So Brooks makes a good point that I can see the game completely getting out of hand in a simulation when this starts to happen.

I don't mean to be a smart ass or anything, but at worst, employ the old "can't-beat-em-join-em" mehodology and "borrow" heavily from other football sims of the past and how they went about handling half/game-ending team decisions to make the game flow at least somewhat recognizable to the real game we're simulating. There MUST be some way!