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Ah, yes, when you name a theological system (er, position) after yourself you're being traditional and when I copy and paste Trent I'm being self-important. Must be because of how much more learned you are, forgive me.
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Am I doing it right?

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Even someone who has supernatural faith can have *more* supernatural faith super-added onto their existing 'amount'. That's what happens, for instance, when a catechumen who already has supernatural faith is baptized.
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Chap. 10. Concerning the Increase of Justification Received

1535 Dz 803

Having, therefore, been thus justified and having been made the "friends of God" and "his domestics" (Jn 15,15 Ep 2,19), "advancing from virtue to virtue" (Ps 83,8), "they are renewed" (as the Apostle says) "from day to day" (2Co 4,16), that is, by mortifying the members of their flesh (Col 3,5), and by "presenting them as instruments of justice" (Rm 6,13 Rm 6,19), unto sanctification through the observance of the commandments of God and of the Church; in this justice received through the grace of Christ "faith cooperating with good works" (Jc 2,22), they increase and are further justified [can. 24 and 32], as it is written: "He that is just, let him be justified still" (Ap 22,11), and again: "Be not afraid to be justified even to death" (Si 18,22), and again: "You see, that by works a man is justified and not by faith only" (Jc 2,24). And this increase of justice Holy Church begs for, when she prays: "Give unto us, O Lord, an increase of faith, hope and charity" [13th Sun. after Pent.].

http://www.clerus.org/bibliaclerusonline/en/dw5.htm

Here is Trent immediately after the section where preparation is described:
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Note the council does not say that justification *may* follow preparation, it says that it *does* follow the preparation just described.
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