From memory the BIG problem for the V-22 when VRS is encountered is that it can happen on one side and not on the other, and I remember that this was the complexity in one of the accidents causing an uncontrolable roll from which the normal recovery action, that of going for forward speed/reducing pitch was not going to work. I would have expected the design staff to have looked at this occurrance and put in a computer programme to either limit the pilots choices (thereby avoiding the situation developing) when selecting a near VRS situation or putting in warning bells to alert of the onset of VRS.
Like all new flying consepts there is a lot to learn and its is either resolved by special flying techniques or by engineering.
There must be handling characteristics inherent in the V-22 which havent yet showed themselves. Thus it will be a long tough learning curve over the next years.
Incidentally does the rotor system have flapping hinges of any sort?