It's always been understood that the fruits of the mass quoad nos
are "throttled" so to speak based on a number of factors. Otherwise, a single Mass would suffice to convert the entire world at once. That is the same kind of argument I made with regard to the fruits of Holy Communion for those who receive at a NOM (on that thread where I was fighting with Sean Johnson about it).
I believe that the fruits of the NOM quoad nos
are next-to-nothing, if not nothing at all. In fact, it might have a net yield of negative graces in that it positively displeases God. So, for instance, those who might participate in even a valid Black Mass would receive condemnation and loss of grace. If in the NOM God sees it as an insult to His Son and to the Holy Sacrifice, it might easily incur His displeasure and lead to a His WITHDRAWING graces from the world.
Similarly the graces received from Holy Communion are throttled ... not only by subjective dispositions, but also by the Mass itself (if it's defective or offered by an unworthy celebrant). I believe, for instance, that if you had a deviant priest (say, a pedophile or Masonic/Satanist infiltrator like Bernardin) that those who receive Holy Communion probably receive less grace even if they have the best subjective dispositions.
Now, this might be perception to a degree, but I don't believe so, but I have sensed that some Masses I've assisted at yielded more grace than others ... with my subjective dispositions being equal.
My experience backs up with Siscoe says here:
The fruit that an individual derives from a particular Mass is not based solely on their personal piety and devotion, which is only one factor that determines the amount of grace they receive. There are other factors as well that have a bearing on the efficacy of a particular Mass, such as the holiness of the priest, the external glory given to God by the ritual, and even the general holiness of the Church in its members at a given time. These external factors affect the amount of grace a person receives, in such a way, that a person can derive more fruit from the devout hearing of one Mass, than from an equally devout hearing of a different Mass.
I believe that the same things holds true for Holy Communion, that the graces received ex opere operato
can be very little if any from the NOM (against Sean Johnson) even if grace can be received ex opere operantis
by the subjective piety of the individual.