St. Thomas on the Immaculate Conception
People who worship Aquinas refuse to admit that he erred big time on this issue. He was one of the main reasons why it took so long for the Immaculate Conception to be dogmatically defined. The fact of the matter is that he did deny it:
Summa Theologica, Vol. 4, Pt. 3, Q. 14, Art. 3, Rep. Obj. 1: "The flesh of the Virgin was conceived in Original Sin, and therefore contracted these defects."
This isn't a matter of something that hasn't been formulated yet. The deniers of Baptism of Desire and Baptism of Blood are claiming that the Church teaching authority hasn't correctly interpreted its infallibly defined doctrines or corrected its most eminent theologians, and that this has gone on for centuries.
The teaching authority is the Magisterium. The word
'magisterium', used by the Vatican Council, means
'teaching authority'. The theologians are not the Magisterium (and if they were, then the Magisterium would be contradictory and schizophrenic), so the "teaching authority" has not "incorrectly interpreted its infallibly defined doctrines."