Using SubjectScheme to manage ishcondition values?

Has anybody used DITA SubjectScheme map to manage ishcondition values? I'm having a hard time figuring out how to use Condition Manager to manage conditions at the product team level. Our options seem to be global management or user/local management, with no granularity between.

I think if we had a product-specific SubjectScheme map controlling ishconditions, each bookmap could reference it (as "resource-only", of course) to provide the right amount of consistency among writers.