All of this was put in place after World War II to centralize power in the hands of the Christian Democrats, and force non-communist parties to go into coalition with them. As all prime ministers for a half century after WWII were either Christian Democrats or from those parties in coalition with them, it worked fairly well. Of course even this had bumps in the road so you have the 1948 elections which the communist/socialist coalition won but which was fixed the other way, a strategy of tension by P2 and the far right being blamed on the far left as the left makes electoral and other advances in the 1970s, plus you have Gladio and secret NATO armies in the wings in case the communists are actually elected into power. Of course being Italian, you know all of this.