My guess is the 'network requirements' are that every second block has to be signed by some king of magic private key. Of course that would be terrible design as the key will leak sooner or later but I can't think of any other way of getting trusted super nodes to contribute to the block chain in the way SC2 seems to have done.
I don't think it requires a common key. It does seem to require making a donation to the central fund though. Assuming anyone could participate as a trusted peer if they wanted, then you have the following dynamic.
Fork A: One hundred independent trusted peers interspersing donations between 1000 generated blocks, means 10 donations each.
Fork B: One clandestine group interspersing donations between 1000 generated blocks, means 1000 donations.
Perhaps that is the disincentive?