I see you mentioned the name Boyd K. Packer. Of all of his quotes about the form of censorship and willing nondisclosure known as 'faithful history" or 'faith-promoting history," one comes to mind when reading your post:
"Some things that are true are not very useful."
Countless official sources for his speech about not telling all: The Mantle Is Far, Far Greater Than the Intellect, but this time we'll go with re-publication of the speech starting at Page 114 of this Institute (i.e., educational materials for college students or to teach college students) publication: http://institute.lds.org/content/languages/english/Institute%20of%20Religion%20Materials/Teacher%20Resources/Religion%20370,%20471,%20475%20-%20Teaching%20Seminary%20Preservice%20Readings~eng.pdf
When I first heard of the so-called “Lamanite DNA” issue I was serving in a Ward Bishopric for the Mormon church. I was devastated and troubled for sure. Then 9 months later I came forward with my devastation/sadness to my extended family. An uncle of mine who is supposed to be an expert on Mormon doctrines/history offered to help. So after asking me a whole series of questions on whether I was obeying all the rules of the Mormon leaders he then sent me a copy of this talk by Packer. I’ve received a copy of this talk from others too. However this talk is non scriptural canon or doctrine in the Mormon religion. And besides I didn’t have the best experience shortly after my “Lamanite DNA” crisis of faith in following some advice of Boyd K. Packer. He had once written that a testimony is gained in bearing it. So when it came my turn a few weeks later to conduct Sacrament Meeting on Fast Sunday I got up and took Packer’s counsel to heart. Sure I brought tears to the eyes of many in the congregation. But I felt something akin to the feeling I normally associate with lying. From that moment forward I’ve never felt comfortable fulfilling any church leadership responsibility in the Mormon church. And BTW its been over a decade since I’ve fulfilled any church assignment of any sort.
And perhaps HERE is the reason for MORMONs to IGNORE their own Organization's teachings:
Professor Robert Millet teaching at the Mission Prep Club in 2004 http://newsnet.byu.edu/video/18773/ <-- Complete and uneditted
Timeline... Subject...0:59 "Anti-Mormons..."1:16 "ATTACK the faith you have..."2:02 "We really aren't obligated to answer everyone's questions..."3:57 "You already know MORE about God and Christ and the plan of salvation than any who would ATTACK you."
Once again Restornu; Thank You! for clueing me into the COMPLETE version of thbis video.