Trent decrees that if you say the sacrament is not necessary unto salvation, then you are anathema. Being Trent's Canon is defined dogma, we are bound under pain of mortal sin to believe this, yet, regardless of your source, you are saying exactly what Trent condemns while using a fallible source which seemingly obviously teaches contrary to Trent.
I am asking sincerely here, do you realize this is contrary to Trent's canon? If not, using only Trent's canon, what do you understand the canon to mean?
I did answer your other points, but this post got so long that I deleted the rest of this post, but we can revisit later if needed.
The canon you quoted said baptism, not the sacrament of baptism.
In the prior section on "The Sacraments in General," it qualifies the statement, by added “or the desire thereof”. Here it the canon:
The Sacraments in General: CANON IV.-If any one saith, that the sacraments of the New Law are not necessary unto salvation, but superfluous; and that, without them, or without the desire thereof, men obtain of God, through faith alone, the grace of justification;-though all (the sacraments) are not indeed necessary for every individual; let him be anathema.
If you interpret that canon as meaning a person can be justified and saved by baptism of desire, your private interpretation will be in agreement with all the catechisms and theologians who addressed it after the council. If you privately interpret the canon differently, you are no different than a Protestant.
I am asking sincerely here, do you realize this is contrary to Trent's canon? If not, using only Trent's canon, what do you understand the canon to mean?
I understand the canons from Trent concerning baptism/baptism of desire to mean exactly what the following three catechisms teach:
Catechism of Pius X: Question: Can the absence of Baptism be supplied in any other way? Answer: The absence of Baptism can be supplied by martyrdom, which is called Baptism of Blood, or by an act of perfect love of God, or of contrition, along with the desire, at least implicit, of Baptism, and this is called Baptism of Desire. Douay Catechism, 17 the century:
Question: Can a man be saved without baptism?
Answer: He cannot, unless he have it either actual or in desire, with contrition, or to be baptized in his blood as the holy Innocents were, which suffered for Christ.
The Baltimore Catechism
Question: How can those be saved who through no fault of their own have not received the sacrament of Baptism?
Answer: Those who through no fault of their own have not received the sacrament of Baptism can be saved through what is called baptism of blood or of desire.
If your private interpretation of the canons of Trent on baptism differs from what these three catechisms teach, please provide a quotation from any Pope or approved theologian after Trent that explicitly disagrees with what they teach. And by explicitly disagrees, I mean one who teaches that a person cannot be justified and saved by baptism of desire or blood, which produce the salvific effect of baptism without the water.