That's a valid concern and freezal got it right: the network had to start centralized and no one's showed up yet with the needed reputation and credibility. I'm going to use every opportunity to relinquish control over 11 out of 12 witnesses in favor of reputable individuals/organizations/companies that are willing to be part of the network. That would make the network only stronger thanks to both their involvement and the network becoming more decentralized.
Thanks for clarifying that. The other concern that keeps coming to my mind is this: what happens if 2 or more of the 12 witnesses goes down (offline) for various reasons (hardware mulfunction, operator not interested in running it anymore, government seizure etc.). Will this cause any network disruption? If yes, what kind of disruptions would that be?