To claim that the subjective dispositions of the recipient effect the justification, rather than the Sacrament itself, is Pelagian heresy.

To say that BoD is an ex opere operantis phenomenon is in fact Pelagianism.

PS -- THAT is why St. Augustine forcefully rejected BoD after battling with the Pelagians.

Ludwig Ott:  "Baptism of desire works ex opere operantis."

This basically means that recipients of BoD effect their own justification.  Pelagianism.  St. Augustine realized this.

Is faith in the Sacrament required for BoD? Heck no! A BOD is guaranteed to work "even though he has never even heard of the existence of the Sacrament of Baptism" - as the scan from this catechism teaches, see item (4). 

How does BOD give grace to a pagan/hindu/moslem/protestant who HATES catholicism (and has no desire to obey the pope), but only "desires God"?  This is where the "rewarder God" heresy pits Catholicism vs God, which is an abominable error.

I mean, I'm guessing Lefebvre had in mind Hindus/Muslims/Prots who had never heard of Catholicism or, at most, had heard some grotesque mischaracterization of it.  I seriously doubt he or any other trad believes that anyone who understands Catholicism and still rejects it has any hope of salvation via "sincerity".

Yes, even Xavier cited a source which stated that those who despise the Sacrament cannot receive BoD.  But many if not most BoDers would not exclude even these from the possibility of receiving BoD.

But what about those who simply don't have faith in it?

I'm asking for a BoDer to explain the metaphysical operation of a Sacrament through space and time to act on someone who's not even aware of its existence  and doesn't believe in it.

It's very much akin to Rahner's "αnσnymσus Christian" theory.

Yes indeed. We are all imbued with the supernatural existential, that uncreated grace that apparently draws us closer to God. 
Everything needed for man to attain Heaven has been fulfilled through the Incarnation. For Rahner, the Passion, Death and Resurrection become nothing more than an aferthought.
What Rahner was trying to take the IDEA of a saviour, one who significant for salvation, and marry it with the concrete person who is Jesus Christ as revealed through Holy Writ and Tradition. He failed. Rahner's Christ is not THE CHRIST, when you get down to the dirty nitty gritty details.
We are all saved, whether we want to be or not, because God has irresistably willed it to be. There is no saying NO to God's grace in Rahner's thought.
I call this "damned to salvation." 

So no one knows ... what BoD is and how it works?  That's rather unusual for a defined dogma.

I'm sure that Baptism is right now saving some Hindu in Tibet, who will shortly be entering the Beatific Vision.

The use of the word “implicit” is grossly wrong.  When modernist heretics use the phrase “implicit faith”, they go on to describe a situation where an ignorant person doesn’t know something about the Church.  But something that is implicit is 100% understood (just not openly expressed).  This is why St Alphonsus’ use of implicit faith is orthodox.  He was speaking of a catechumen who was learning the faith but who just hadn’t formally asked to be baptized.  But such a one a) knew exactly what baptism was, b) knew what it meant to be a member of the Church, and c) by their actions in learning and asking questions of the Faith, was passively implying they wanted to join the Faith.  In other words, their actions were speaking in place of their words.  
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That’s what implied means.  A “100% understanding” is part of the meaning of the word. 
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What modernist heretics have done is apply V2’s “subsists in” theological error of Christianity to baptismal faith.  In the former, they have erroneously made belief in any type of Christianity salvific.  In the latter, they have erroneously made desire for any type of “god” or “truth” a baptism.  Both of these errors are necessary for the freemasonic one-world Church to be born.