Great, thanks for the feedback. In working with Nancy on HEART stuff this weekend, I found that this rhetorical work was helping. Note that in RReg 02 (and actually in Core 09 as well), this got morphed a bit further to this formulation:
"Any one resource that the resource server has registered for protection MAY consist, from the resource server's perspective, of multiple parts, or have dynamic elements such as the capacity for querying or filtering, or otherwise have internal complexity. It alone is responsible for maintaining the necessary mappings between these complex representations (which might be expressed, for example, as different requests coming from the client) and the single resource identifier known to the authorization server."
We might want to go back and make this more active-voice, as in the original below. ("The resource server MAY register for protection a single resource that, from its perspective, has multiple parts...")