OFF TOPIC? I don't really think so. But please ignore at your pleasure
I don't know if it's true or not. But I have heard that they teach bank tellers to distinguish counterfeit by having them study real money bills.
Could it be that the greater danger is not one of the two given options but instead lack of knowledge of the real living Jesus and the real Catholic Church?
I was surprised to find out that even after many years, I did not have a good understanding of the most fundamental errors of Luther and Calvin until having read a talk/essay by Fr. Hardon on Lutheranism (Luther also believing in Total depravity of man, like the TULIP Calvinists) and until having read the CCC section on 'actual' and 'habitual' grace.
Then I was further surprised to find out that the Church apparently hardly bothered to make much of a distinction between 'actual' and 'habitual' grace until the Council of Trent. Now I don't think that I am so naive to believe that every Catholic needs to study all the heresies in the world to be protected. Somehow it seems plausible to me that if a Catholic is properly Catechized AND has a nourishing diet of devotions (sacrements and prayers, etc.) then in most cases his "sensus fidei" should protect him from the majority of tricks of the devil. People are going to keep reinventing old heresies with new names and with different combinations and permutations of old concepts to lead us into the "brave new world" or some new kind of "crazy wisdom" (e.g. 'word of faith', 'prosperity', 'new age', counterfeit revival, LGAT's, abrogation [talk about 'crazy wisdom'] and sharia, etc.)
Now obviously I don't fault the Catholic Church for not emphasizing a helpful concept such as 'habitual' grace much until Trent. Truth is One, but heresies are potentially almost endless. Those priests who did still have an undebilitated 'sensus fidei' would not have needed to have such a vocabulary including the word 'habitual' grace, to have resisted confusion and infection.
But I happened to learn from Fr. Blankenhorn's article and lectures on St. Dominic that Dominic was a cathedral canon (priest) in a fellowship of such priests at the cathedral and that such priests at that time were among the relatively few in those days who had the time and training to become well founded in Catholic theology AND that most Catholic theology (i.e. for canons) at that time was Catholic bible study. Furthermore, in terms of formation, as a fellowship of priests they chanted the Divine Office. Thus St. Dominic (esp.) and also his fellow canons were well prepared in catechism/theology and in devotion (Divine Office) to fight the Albigensian heresy when the terrible apostasy and destruction caused by this cult came to his attention on his journey to Denmark, I think.
I'm old enough now that I don't blindly trust my body to absorb all the punishment of junk food I gave it in the past. Having reduced my intake of junk food, I find that I don't crave it as much as I used to, so it doesn't really taste that wonderful. I hope that I will also be able to increase my appreciation of healthy simple plain food. I hope that I will do the same with my spiritual diet so that my "sensus fidei" will be healthy enough to detect 'spiritual junk food'.