I couldn't find a post for this topic, so here it is.
One of the issues presented was around wrangling the various online channels to onboard people to the community. e.g. Facebook, LinkedIn, Twitter, etc.
Randall mentioned that it was not necessary to use all of these channels individually, but rather you can use the channels to funnel people towards the one channel that you want to use and have control over.
I would consider "channel fragmentation" as a bug in your community. It's not a problem with the technology; it's a problem with the culture of the people.
As a community manager it is not always necessary to allow people to be totally comfortable. Community has a delicate balance between the power of the head and the inclusion of the body. It becomes a bit dangerous when the body has too much autonomy. If the members of the community are not willing/able to learn and comply with the culture and methods that facilitate vision of the community, then perhaps those are not the type of people you want to be in your community.
Then again, not all communities seem to have the luxury of being selective.