I don’t think they are talking about tempered discussions between people of opposing viewpoints who nevertheless respect each other. They are counseling against contentious adrenaline laden verbal sparring matches.
I left the church during this time after finding out oabout the false prophesies of Joseph Smith, and Brigham Young, and the thug-like and murderous behavoir.
Here are a few quotes that really stick out in my mind...
I discover that some of the Eastern papers represent me as a great blasphemer, because I said, in my lecture on Marriage, at our last Conference, that JESUS CHRIST WAS MARRIED at Cana of Galilee, THAT MARY, MARTHA, AND OTHERS WERE HIS WIVES, AND THAT HE BEGAT CHILDREN. (Journal of Discourses, Vol. 2, page 210)
Brigham Young, answering critics who claimed polygamy as a relic of barbarism: Yes, one of the relics of Adam, of Enoch, of Noah, of Abraham, of Isaac, of Jacob, of Moses, David, Solomon, the Prophets, OF JESUS, AND HIS APOSTLES. (Journal of Discourses, Vol. 11, page 328)
"President Smith then stated that the meeting had been called, because God had commanded it; and it was made known to him by vision and by the Holy Spirit. . . . it was the will of God that they should be ordained to the ministry and go forth to prune the vineyard for the last time, for the coming of the Lord, which was nigh even fifty six years should wind up the scene." (History of the Church, Vol. 2, page 182).This prophecy was spoken by Joseph Smith in 1835, and recorded by Oliver Cowdery. The fifty-six years were passed by 1891.
Deuteronomy 18:22 (King James Version) 22 When a prophet speaketh in the name of the LORD, if the thing follow not, nor come to pass, that is the thing which the LORD hath not spoken, but the prophet hath spoken it presumptuously: thou shalt not be afraid of him.
The LDS Church wants these secrets and thousands more like them to continue to be kept from the current membership, that is why they have ordered members to stop arguing doctrine with true Christians.
I'm not sure I agree that's all that's at stake.
The Saints quickly get into trouble when they run into someone who is well informed about their religion.
For example, this individual might bring up topics such as the dozens of obvious errors in the Book of Mormon, the Book of Abraham, the thousands of changes to Mormon Scripture, the nine different versions of the First Vision, sexual perversion (including D&C Section 132), the obvious contradictions among Mormon scripture, the failed prophecies by Joseph Smith and Brigham Young, the Adam-God doctrine, the Kinderhook Plates, the United Order, the Kirtland Safety Society, the sins committed in the time of preexistence by the spirits born into bodies as African-Americans, the Satanic Mormon Temple Ceremony, the LDS' connection to the occult, and much, much more.
Articles posted earlier on this forum indicate LDS membership may be overstated, and there may now be more ex-Mormons than practicing Saints. And much of this is due to their exposure to the truth.
I therefore can easily interpret the article as advising Mormons to avoid discussions with people who have opposing viewpoints because they might be handed facts which will cause them to loose their faith in Joseph Smith and their Church.