The "one-off" explanation would fly better if this game had been in the middle of the season where the D had only a week to prepare, But that was not the case.
These were bowl games from 3+ years ago, but both Iowa and LSU faced Georgia Tech, a triple option team. With time to prepare, both of them shut the attack down.
In the end Navy got the ball quickly to the edge and had success. That has me a bit uneasy until I see the back 7 perform in next week's game.