No, I haven't, but I have heard plenty of people insist that the only real authority is one's own opinion.
Yup. They're good at quoting Man has the right to act in conscience and in freedom so as personally to make moral decisions but not so good at remembering Conscience must be informed and moral judgment enlightened or This ignorance can often be imputed to personal responsibility. This is the case when a man "takes little trouble to find out what is true and good, or when conscience is by degrees almost blinded through the habit of committing sin." In such cases, the person is culpable for the evil he commits.