Stubborn, there's 2 issues to the whole BOD debate:
1. Can desire/vow alone provide justification?
a. Many saints say 'yes'; Trent does not clear up this answer. An honest reading of it, (especially in Latin), does not definitely say.
b. Even if one agrees that a 'yes' is a liberal answer, I do not think a 'yes' is a major problem, considering all of the circuмstantial evidence which agrees with it.
c. The proper translation is 'vow' and this would ONLY apply to catechumens who have ALSO fulfilled previous requirements of Trent, for baptismal preparations.
d. Conclusion - the # of people who fall into this category is very, very small.
2. Can justification provide salvation/heaven?
a. Absolutely, positively not. Trent doesn't even hint that this is possible.
b. Some saints propose it's possible but this was before Trent.
c. These saints also contradict themselves, by saying BODers have to go to purgatory first, or some say they don't.
d. St Alphonsus is the only major saint post-Trent who argues it's possible but 1) I question the translation because 2) it contradicts his other writings.
e. Conclusion - There is no major teaching (i.e. it's not 'de fide') that an unbaptized, justified person goes to heaven. The evidence says they go to Limbo.
Being with how many people today hold a VERY liberal (probably heretical/pelagian) view of BOD, I am willing to grant the "justification by desire/vow" only for the sake of pulling these people back to sanity and orthodoxy. Because if you just 100% reject "desire/vows" they will mentally shut down and stop thinking, so they won't listen at all.
In this day and age...I don't see much of a danger to admitting the *possibility* of a formal catechumen (who has rejected Hinduism, Muslimism, Judiaism, Protestantism, Paganism, etc) and who formally, openly, explicitly desires baptism and is taking classes to become a catholic. Anyone who fails to meet any of these standards is not a "catechumen" and BOD would not apply to them.