Well, you are free to disagree - but if you want to depend on a contrition which "sometimes happens" as assurance that your sins are forgiven, and then call that a COD - and Trent an imbecile or a deceiver, then feel free. I admit it could sometimes happen - but a "COD"? Never.
We cannot depend on any such thing. In fact, depending on perfect contrition would in fact ironically undermine the desire to receive the Sacrament and render it incapable of restoring one to a state of grace (as Father Feeney famously said about the desire for Baptism).
The fact is Trent does not teach of anything even remotely called a COD for a reason - because there is no such a thing - I say that whoever constantly preaches that there is such a thing as a BOD or even a COD should expect God to give them the opportunity to practice what they preach when their last hour nears - they certainly won't be needing the last sacrament after they've been preaching that an infidel can be rewarded salvation without any sacrament at all.
You make an interesting point. Confession of Desire should be considered a term completely repugnant to Catholics. Yet why is Baptism of Desire any different? Only because people coined the term and kept repeating it. The minute you would start talking about Confession of Desire as such, you would start undermining the Sacrament itself ... just as the term BoD does for Baptism. So I understand your visceral repugnance to the notion. In fact, if anyone started talking about CoD, I would immediately want to slap them down.
Another interesting point to consider is that Trent teaches there's no such thing as the Sacrament of Confession for those who have not been Baptized. So for any unbaptized person who would fall from a state of grace (allowing only for the sake of argument that they could be in a state of grace to begin with), there would be absolutely no remedy.
Moreover, neither before the coming of Christ was penance a sacrament nor is it such since His coming to anyone before baptism
Notice, there is NO SACRAMENT OF PENANCE to the unbaptized. So how then could the unbaptized be restored to a state of grace by a desire for the Sacrament of Penance? They are incapable of receiving the Sacrament of Penance.
That's yet another argument against salvation by so-called BoD.
BoDers claim that perfect charity alone (without the Sacrament of Penance) can restore to a state of grace. That's condemned by Trent. Trent teaches that the fruits of the Sacrament are applied via the desire for it and that perfect contrition alone does not suffice. But how can the fruits of the Sacrament be applied to a soul who is not capable of receiving it (the unbaptized)?