Just two comments:
1) It is extremely unfair - not to mention inaccurate - to compare Fabio Leite to Jack Chick.
2) I actually agree with stashko (waits for lightning bolts! ) - there ARE an awful lot of spurious visions of Mary which deceive a lot of people, and may well be demonic. Many great RC saints such as Teresa of Avila and John of the Cross advise us to reject ALL such visions, just to be safe.
1) I don't think that Fabio is Jack Chick. In fact, I think that most Fabio's posts at OC.net are fantastic. But in this particular thread, I do believe that Fabio's tactics
are similar to the tactics
of Jack Chick.
2) Yes there are some that are not genuine, but I doubt one that has been approved by the Church, and carries with it such universal Catholic support would be demonic. "The Church of the Living God, the Pillar and Foundation of Truth."