I think the predominance of T-38 studs going to the U-28 had more to do with the situation starting back in the '09 classes. Maybe 1 fighter per class, and the whole "universally assignable" (heavies) thing didn't really come to fruition until the end '09, beginning of '10 classes.
Simply put, the need for fighter pilots slowed drastically but the need in AFSOC was growing at the same time. Easy solution.
Just my thought.