Pretty in Punk - Oral Histories and Feminism

I'm currently reading Pretty in Punk; Girls' Gender Resistance in a Boy's Subculture by Lauraine Leblanc for my thesis. Leblanc relies heavily on interviews she conducted with self-identified punk girls in four different cities (Atlanta, Montreal, San Francisco and St. Louis) between 1993 and 1995. In discussing her methodology, Leblanc discusses the shortcomings of ethnography/oral history as a research method. Some of the issues she addresses, such as relying on interpersonal relationships that may bias the information gathered in the interviews, are highly relevant to me as I begin to consider my own methodology. Most of the people I plan on interviewing from Rock Camp are personal contacts, or friends of friends. Leblanc's methodology highlighted the importance of considering one's own subjectivity in relation to a project, both in the ways in which it aids in gaining access to communities and interviewees, and in the ways in which it hinders a multi-faceted approach to the project. What are the advantages of using a participant observation model, in which the researcher does not know the community personally before beginning to research? What information can you only gather if you know the community and its participants on a more personal level?