A question about being self-referential in Networks of learning

This is a question I posed to George Siemens on May 13th.

Have you any references to scholarly work that would address the question of isolationism and self-referentialism in communities of learning.
I have looked at Dave's edtech talk (lurking only) and a a few others and there seem to be very few voices of descent. I was just wondering if persons of dissenting opinions would be ignored, banished, or quit the communities of their own volition and how new or radical thoughts would enter the discourse if everyone is in general agreement all the time. From what I know of the scientific field it is the imaginative and oft-time radical ideas that truly make a difference in changing ideas and mind-sets.

I have found very little information on this topic to date. Anyone have a link to some ( text based) resources?