Iowa’s comeback made it nine losses for Nebraska. No matter how you slice it, losing nine games is not progress. So this is how the 2021 season ends. Not with a bang, but a whimper … and a one-score loss. Another sequel in the same movie franchise we’ve seen all year. A tough defense that is strongest when it counts. An offense that is weakest when it counts. Special teams that are the equivalent of a toddler with a loaded handgun. A butterfly flaps its wings and a single snowflake becomes an avalanche. Fans, coaches, and players wear a look that is part deer in headlights and part “Groundho…