The mini block rear spring is used in several FWD vehicles around the world and the main reason is the great characteristics for suspension packaging, wheel travel and Ride & Handling compromise for driver load up to full load condition.
The rear suspension rate for driver or driver plus passenger load condition is tuned usually without major penalties, being necessary to perform the correct balance between front and rear axle vibration / grip.
While the vehicle is loaded at the rear seat and trunk, the rear suspension rate changes, which is great for lower vehicle pitch angle, resulting also in smaller jounce suspension travel.
The critical point is the how to achieve the optimum suspension rate as the vehicle goes heavier for a good Ride and Handling compromise. It's important to remember that this higher suspension rate for jounce motions will influence the vehicle for driver load condition when the vehicle rolls with lateral acceleration or passes through a speed bump.
The vehicle spring center concept was refined and applied in several projects, resulting in shorter development time and better overall Ride & Handling compromise.