The Philosophy of Communication---Chapter 2

After reviewing Chapter 2, there comes a question for me: what is the essence of the philosophy of communication and what does the role of narrative in communication ethics in social life.
Here are some basic descriptions of the philosophy of communication and narratives.  In chapter 2, it says the value of  the philosophy of communication is " gives life richness, depth, texture, and meaning. Without a philosophy of communication, we meet only a technical manual or a set of isolated recipes that assumes that we already know why what we are doing matters"(p 35); also, the philosophy " understanding of communication ethics provides the 'why' for communicative action, and applied communication carries the “why” into interaction with others"(p 35).  Talking about narrative, there is a brief introduction on page explains narrative as "a story agreed upon by a group of people that provides limits within which we dwell as embedded communicative agents", and narrative is capable to "do change from the actions of communicative agents and shifts in the historical moment; ideologies resist alteration from the outside and stories fail to move people to the point of active support".
As the descriptions above, there should be a question that who will use the philosophy of communication and narrative for what purposes?  If narrative targets to limited groups of people, change communicative agents and lead people to support a specific idea, and the philosophy of  communication provides the necessities and reasons of communicative actions, how can we understand some historical and political documentaries?  We clearly know that those kinds of documentaries aims to educating citizens and solidifying governing for people who are in power, based on the influence of the philosophy of communication and narrative, we surely can suspect whether all these documentaries are reliable and true.  Taking Holy Bible as the example, there are different explanations about the Holy Bible from different genres, but how can we distinguish which is the most accurate explanation?  From my perspective, it depends on the government.  To be specific, what is the effect the government expected by supporting one specific explanation or what is the influence on the public the selected explanation can bring, and what is the government's the final purpose by selecting one explanation.
Or maybe we can think about another question: after learning the knowledge of the philosophy of communication and narrative, we know how to communicate with others more effective; meanwhile, how the philosophy of communication and narrative have influenced our life.  We can utilize all these knowledge, and we can also be made full of by these knowledge without consciousness, especially in political and social life.