To ride the curbs without disturbing the car too much you need the suspension to be able to suck up the impact whilst leaving the body in the same place. To achieve this you need softer springs (easy to compress), low damper compression (allows spring to compress quickly and unheeded) and a medium/high damper extension(keep the wheel following the terrain). The downside to this is that the body will roll in the corners losing speed in mid/high speed bends. You can counter this to some extent with high ARB rates but the car will become slightly twitchy due to less controlled lateral weight shift.
Its all about minimising the impact, hitting a curb in a stiff car will cause a massive shock to travel through the suspension to which ever wheel is carrying the highest load (usually outside rear but depends on what phase of cornering you are hitting the curb)). If the suspension can't react fast enough then it will be bypassed by the force, travelling straight through the car body and onto the load bearing wheel. A tyre can only handle so much load before it lets go and high force impacts will break this limit very quickly making the car lose traction in an unexpected manner.
Basically you need to think about the smoothest way to deal with the forces, the suspension needs to be able to smoothly transfer energy without overcompensating and starting to wallow about like a frisky hippo.
You also need to consider how much high speed stability these changes may lose you.
Speed/time gained by riding curbs Vs. Speed/stability/time lost in faster sections
The best setup is always a compromise of both, there is no fix all solution that suits every situation, just a case of finding out which is faster and more suitable for you.
