Every winter, a wave of programs change head coaches. The assumption inside a lot of front offices is that the new hire's scheme is what shakes a roster loose. Pro-style teams that install an air raid lose their downhill runners. 4-3 teams that flip to a 3-3-5 lose linebackers who don't fit. We tested that assumption directly against 296 FBS head-coaching transitions from 2021 to 2023, isolating scheme change from staff change for the first time in our research library.
The scheme change turned out not to matter, statistically. Programs that shifted their offensive identity by a wide margin, measured by year-over-year swings in offensive line yards and power-success rate, showed no meaningfully different portal departure rate than programs that kept the same offense.
What did move the number was simply whether the head coach changed. Programs with a new head coach averaged 28.33 transfer departures the following season. Programs that kept the same head coach averaged 25.12. That is a 12.8% increase tied to the coaching change alone.
That is a real signal for anyone planning around a coaching change, whether you are the incoming staff working scholarship math or a rival program scouting the portal for opportunity. The instability that triggers exits is not about which plays get called. It is about who is calling them.
Methodology: we cross-referenced head coaching changes (college_coach_seasons, 2021 to 2023) against FBS offensive scheme shifts (offensive line yards and power-success rate, year over year) and portal departures by position group, covering 296 FBS program-season transitions. Full finding: RI-RF148, approved for publication in our research library.