Your kidding, right? it clarified all things synergistic.
Sure you can say Trent anathematized anyone who would hold to full Pelagianism and deny the necessity of grace. But that comes only by using Romes false definition of what is grace, and her lack of understanding of the sufficiency of God's grace to PERFECTLY save a people through Christ.
The very attempt to deny a Pelagianistic synergism on the part of roman catholics is simply irrational....You proclaim God's grace and then limit and deny it's sufficiency...You claim your works are prompted by grace, in doing so you are missing/losing the freedom of God in salvation and forwarding mans freedom as the determining point of salvation (ie. the successfulness of grace)
When you take Rome's doctrine of the man's will and its sacraments serious, you are denying God's freedom to have efficient grace to accomplish His own purposes.
all grace is efficacious in itself. Whether it is efficient on us depends on our disposition towards it. Its not the grace itself that is "defunct" it is our disposition and sin that pushes it away from us. But sin doesn't take away the preservation of the freedom of the will acted upon and working with grace, especially efficacious grace
For if grace, instead of elevating and ennobling free-will, subverts it, then all the Biblical counsels and prohibitions relative to the affairs of salvation, goodness, and morality which can be accomplished only with the help of efficacious grace, become vain and meaningless. Only in the event of the will remaining free have the words of Christ any significance: "If thou wilt enter into life, keep the commandments". The Council of Trent simply affirmed this as the bible would not have put such large emphasis on the keeping of commandments or working out salvation with things like fear and trembling, following moral precepts, avoiding fornication, etc. None of these would have any meaning if there were not free will.
Grace is always the first cause. But God respecting the nature of things and its order , moves necessary agents to necessary, and free agents to free. Grace depends on the fact that it is given under circumstances that God foresees to be congruous with the dispositions of the person receiving the grace. For it is not the will which by its free consent determines the power of grace, but conversely it is grace which makes the free good act possible, prepares for it and co-operates in its execution. The infallibility of the success, which is contained in the very idea of efficacious grace, is not to be explained by the intrinsic nature of this grace, nor by a supernatural but rather by the virtue of which God foreknows from all eternity whether this particular will would freely co-operate with a certain grace or not
I myself think the Molinist approach is the most logical. Congruism also. Whereas the Thomist and Scotist approach seem too rigid and at times almost calvinistic. All schools cannot clearly explain the operation of God's grace however. So go to far to the left(pelaganism) while others too far right(hyper-calvinism). But it only goes to show how limited human beings are in trying to understand something as complicated as the operation of grace. Scholastics can only go so far in this area.