The master model concept is simple.  Your part resides in its own file, and all subsequent assemblies, detailing, etc reside in separate files.  For example, when detailing a part, you bring it into a drawing file as a component, instead of creating a drawing in the part file.

The master model concept does go one step further. For concurrent design, a large assembly (like a vehicle) has many systems that are not complete at the same time.  As parts are created, each designer in a large engineering group can see the changes as they occur by using load options.  Load options can be set to Latest released, Latest working or As saved.  This allows an assembly to load in a incomplete state (by using latest working)and allows the design to continue without waiting for each system to be complete. To view an assembly as it was saved at a point in the past (when the file was released) , an "As saved" option is used when loading.  To view the most up to date version, a "latest working" load option is used.  Load options can also be set in an order of priority. (latest released then load latest working)

The drafting file in the master model concept contains a component (like a small assembly) so that a drawing can be started even if the system is not complete. (two people can't work on the same file)

Does this make any sense?

Peter