St. Louis de Montfort seems to think so. In True Devotion to Mary no. 145 he says
§ 1. She purifies them [our good works] of all the stain of self-love, and of that imperceptible attachment to created things which slips unnoticed into our best actions. As soon as they are in her most pure and fruitful hands, those same hands, which have never been sullied or idle and which purify whatever they touch, take away from the present which we give her all that was spoiled or imperfect about it.
But specifically regarding our own intentions, he says in no. 222 that
Since you do everything through the Blessed Virgin as required by this devotion, you naturally lay aside your own intentions. You abandon yourself to Our Lady's intentions even though you do not know what they are.
At the beginning of 145 he notes the caveat "if he is perservering [in this true devotion]," so one still needs to be actively ensuring his devotion is not a false one.
St. Louis de Montfort also says in Secret of Mary that "the holy slavery of love"
Purifies and Embellishes Our Good Works
- 3° To consecrate ourselves thus to Jesus through Mary is to place in Mary’s hands our good actions, which although they may appear to us to be good, are often very imperfect and unworthy of the sight and the acceptance of God, before whom even the stars are not pure. Ah! Let us pray, then, to our dear Mother and Queen, that having received our poor present, she may purify it, sanctify it, embellish it and thus render it worthy of God. All that our soul possesses is of less value before God, the heavenly Householder, when it comes to winning His friendship and favor, than a worm-eaten apple presented to the king by a poor farmer in payment of the rent of his farm. But what would such a farmer do if he were wise and if he were well liked by the queen? Would he not give his apple to the queen? And would she not out of kindness to the poor man, as also out of respect for the king, remove from the apple all that is worm-eaten or spoiled, and then place it in a gold dish and surround it with flowers? Would the king refuse to accept the apple then? Or would he not rather receive it with joy from the hands of the queen, who favors that poor man? “If you wish to present something to God, no matter how small it may be,” says St. Bernard, “place it in Mary’s hands, if you do not wish to be refused.”
Fr. Maximillian Kolbe, O.F.M., letter 878 from Krakow, August 22, 1939, to Niepokalanów, subscription*:
Let us pray that the Immaculata may purify and raise our intentions more and more.
*"valedictory formula at the end of a letter"