> (I'm one of the architects of the Ripple network.)

Please see the thread linked to above. There were several trust topologies given than are obviously non-convergent in your model and you appeared to have no answer for them.

Effectively you have ripple servers which must have central selection/control (or the system is not guaranteed to converge), and they can set balances to whatever they want. ... and then clients that simply believe the majority of the servers they are pointed at.