So i believe you have not completely understood the concept of CRM.....
CRM was "Crew Ressource Management" in the old days-based on NASA research stating that there were many accidents/incidents based on communication problems between the two pilots.....old Captains "knowing it all", and young Copilots "too scared to speak up"....thats where it started...then it became "Aircrew Ressource Management" when they understood that the Navigator/Engineer is also part of this team, and has his role as well...
Then it stretched to the cabin crew....the ATC and even the guy driving the push-back truck.....
It is NOT "Cockpit Ressource Management".....it deals with all kind of communication between anyone involved in the flight...
MCC is the specific training of someone who is just a pilot (single pilot that is-like we all do at the beginning of our career) to deal and interact with a second pilot on board-depending whether you conduct VFR or IFR operations.
You would be surprised how many single pilot trained pilots fail to work in a crew...