Pyne is the qb because of injury, not because he won the job. Rees/Freeman picked Buchner because his skills sets are better overall all than Pyne. Rees/Freeman then slimmed down the offensive scheme when Pyne became the QB.
If Pyne had played OSU and Marshall, we don't know what that would have looked like.
If Buchner had played with same game plan at Pyne -- short, very low risk passing -- we don't know what that would have looked like.
If Buchner had played with the offensive oline performance that Pyne did, we don't know what that would have look like.