The fact that you have to switch the titles around to make it make any sense indicates that it actually is pretty unusual.
Reporting to a "technical head coach" until the summer (then what happens?) is unique. It doesn't mean it's destined to fail but it is the weirdest system imaginable. If a DoF is set to leave in summer it's obvious what happens next - a new DoF comes in. If a "technical head coach" leaves do we advertise for a new one? No, probably not, since it's made up.
This is the biggest problem of all. He utterly failed at full-time management, completely and totally, commanded zero respect from his players, set them up badly, and suffered a string of dreadful results. Because he's a nice, driven guy and because Billy's lurking in the stand like the Phantom of the Opera he's going to suddenly undo all that? Aye, stranger things have happened, maybe he'll prove me wrong, but IMO his limit is League One with a part-time squad, a big budget, and zero expectations of success.