You can't leave off that phrase. There is historical, theological and Scriptural evidence that "desire" can obtain forgiveness of sins (i.e. justification). The problem with modern-BOD'ers is, they superficially argue that "Well then, if you are in the state of grace, then you go to heaven, no?" This over-simplifies the importance of Baptism (and it's multiple effects) and also over-simplifies what St Augustine, St Ambrose, St Thomas, St Bellarmine, St Alphonsus...and most importantly, Trent (etc etc etc) taught on the matter.
I left it off only for the purpose of the question. For the sake of clarity. To get eyes off of the word "desire" in an attempt to get people to understand that Trent is saying justification cannot be effected without the sacrament.
My thinking is once this is understood as Trent means it to be understood, which is literally that there is no justification without the sacrament, then they will understand that "or the desire thereof" in fact condemns a BOD/BOB, and any and every other idea that leads to justification without the sacrament - but particularly they singled out a desire thereof.
If you agree that Trent is saying that justification cannot be effected without the sacrament, then for the purpose of the question, "or the desire thereof" is irrelevant - the reason it is irrelevant is because justification cannot be effected without the sacrament. Period. All the words "or the desire thereof.
Lad says justification can be effected with a BOD/BOB, so what he is saying is that justification in fact can be effected without the sacrament - which is a direct contradiction of Trent, which is why I asked him to explain.