Oral History and the grand scale.

Frisch's piece A Shared Authority focused upon the use of oral history. He especially focused upon how television used this type of history.
Later in his work, Frisch brings up the concept of using oral history in the Vietnam documentary weakens it, not allowing for a proper critical assessment. He claims that exclusion of sources comes from the sheer use of oral history. He argues that various privileged and non-privileged will not be part of the analysis due to the nature of oral history.
While exclusion does happen, it is part of the oral history in general. Oral history relies solely upon the memories of a person or a group of people. It creates a very intimate feel when it comes to oral history, that the person would not know everything because of time, and their own situation during an event. Oral history acts as an excellent source when working with a specific area, but when dealing with a large concept, the ability of an oral history to contain rich information strains.
With this strain, more oral histories an needed. With more oral histories, there might be agreement or disagreement depending upon what is found. When it comes to creating a narrative, the creators must decide what must be included and excluded. This leads to more omission and can support the argument that oral history disallows for critical assessment.