Some good breakdowns in this thread. I think that the consistent running into a stacked box thinking that everyone will execute at the level required to be successful is a daunting task. It is what the Iowa defense wants the other team to do.
Think about that concept, the Iowa offense is designed to run exactly what the Iowa defense wants an offense to do.
At some point in time you have to lighten that box somehow. Setting up for the 1-2 plays that can be big plays doesn’t leave much room to overcome the drop, the overthrow, the whif by an olineman etc.
Execution can make a run into a stacked box work and that can be demoralizing to the defense but the reality is Iowa is rarely good enough to do it on a consistent basis.
Kind of ... the Iowa D attempts to make an offense have to run a lot of plays and earn every point they make. The D doesn't necessarily care if they give up smaller gainers ... but the objective is to never give away "easy points."
This limits the number of possessions that EITHER team can have. This suppresses the score of the game - and, by default, can help keep Iowa in almost any game.
Furthermore, the objective is to force the opponent to get impatient. Because Phil "believes" so much in "zone-eyes" ... impatient, errant, or tipped balls all can fall prey to one of Iowa's "ball hawks." Consequently, not only does Iowa's D force opponents to earn every score ... the D tends to get a lot of take-aways. Thus, while Iowa's style of ball attempts to limit the number of possessions - when Iowa's D is working as intended - it still tends to lead our O to have the chance to benefit from MORE possessions.
As is also well-known by Iowa's fanbase - the Hawks are also adherents to "Punting is Winning!" This is classic field-position football. When the opposing O is stuck deep in their own territory - they tend to be more careful with the ball (because turnovers can be more catastrophic). Consequently, opposing offensive play is more predictable ... and that typically makes it easier for the D to force a punt.
As for Iowa's O ... the expectation and/or philosophy isn't at all to patiently grind down the field. Our multi-TE formations tend to force opposing Ds to play with their "big" personnel. That then schematically leads to mismatches in coverage. That gives us ONE means of getting chunk plays and flipping field position.
For Iowa, while it's advantageous to score (for obvious reasons) - the objective, at the very least, is to flip field position. To Iowa, punting can be a good outcome if it helps us pin the opposing O deep in their own territory. To complement the objective of limiting the opponents possessions - ideally the O chews up clock as it attempts to flip field position or score. The Hawkeye philosophy here is NOT predicated upon running a lot of plays (like some teams) ... but rather to be very deliberate in its pace (i.e. huddling and whatnot).
If the Iowa O is doing its job and AT LEAST flipping field position - this complements the D - and more likely will help the O to benefit from more short-fields. Short fields then typically equate to points - field goals at the very least.
However, the Iowa O is also about establishing tendency so that it can "catch the opponent" with eyes in the backfield - thereby giving the opportunity for a scoring play with play-action. Thus, the Hawkeye O is reliant on rare-events swinging the momentum in the game. If and when Iowa manages such plays - this completely complements the rest of the game-plan ... because then the opposing O is more apt to press with the ball in the passing game. With our "zone eyes" ... such pressing CAN potentially lead to more picks.
Thus, the point being - Iowa's D is required to be disciplined AT ALL TIMES - because we are trying to force the opponent to be consistent and methodical.
However, the premise of the O is NOT necessarily to be consistent and methodical (although that obviously is ideal if it CAN be) - but rather to flip the field position, chew up clock, and hopefully lull the opposing D into biting too much on the tendency that WE DICTATE (which can then lead to big, game-changing plays).