He does have several years as a position coach, and did help bring about a very good offensive line.
He was an actual OC for 2023 only. Previously, he had two years of co-OC experience. I understand Michigan wanting to keep the HC job for a "Michigan man," but my opinion here is that they settled for the easy way out.
He's going to have a hard time in 2024, since there's a lot of talent leaving that team for the NFL or the transfer portal, especially his top tier QB.