These case studies highlight the extremely limited transferability of these models to classes of reactions that are nevertheless expected to share many essential mechanistic features with the training reactions. For example, many reaction mechanisms are expected to be conserved regardless of molecularity. Similarly, many small and large molecules should exhibit comparable activation energies for reactions with conserved mechanisms. The lack of transferability in these cases studies speaks to a gap in the current architectures. Based on the class-based reaction modeling of experts, this gap should be addressable, but it will require better regularization or additional architectural developments to promote mechanistic transferability.