Let us be clear about this:
DISC failure is unlikely to ever be contained because of the size/mass/velocity of the disc fragments. The mitigation for this is to make a disc failure very unlikely. The sacrifice of turbine blades by interference with stator parts is a small price to pay in protecting the aircraft, even if it results in a lesser-energy uncontained failure.
On the other hand, BLADE failure is generally containable, or at worse, a low-energy case penetration.