Fairburn's Article from March 2019   https://theathletic.com/838469/2019/03/06/it-was-a-perfect-storm-how-jim-kellys-usfl-seasons-changed-the-course-of-the-bills-and-pro-football/   While some of that was cutting edge, the route adjustments are what separated the offense. Receivers and the quarterback would each read the coverage on the fly after the snap. On a given play, each receiver had a different route assignment depending on the coverage they saw. The quarterback and r