I've shamelessly borrowed the following from Daniel C. Peterson, Professor of Islamic Studies and Arabic at Brigham Young University. The full article, entitled "Reflecting on Gospel Scholarship with Abū al-Walīd and Abū Ḥāmid," is to be found at the excellent online journal Interpreter: A Journal of Mormon Scripture, to which you should also donate.
Professor Kimball explained what he called the "three levels" of Mormon history, which he termed Levels A, B, and C. (Given my own background in philosophy, I might have chosen Hegel's terminology instead: thesis, antithesis and synthesis. Those terms seem to me to catch very neatly what Professor Kimball had in mind.)
Level A, he said, is the Sunday School version of the Church and its history. Virtually everything connected with the Church on Level A is obviously good and true and harmonious. Members occasionally make mistakes, perhaps, but leaders seldom, if ever, do. It's difficult for somebody on Level A to imagine why everybody out there doesn't immediately recognize the obvious truth of the gospel, and opposition to the Church seems flatly satanic.
Level B—what I call the "antithesis" to Level A's "thesis"—is perhaps most clearly seen in anti-Mormon versions of Church history. According to many hostile commentators, everything that Level A describes as good and true and harmonious turns out actually to be evil and false and chaotic. Leaders are deceitful and evil, the Church's account of its own story is a lie, and, some extreme anti-Mormons say, even the general membership often (typically?) misbehaves very badly.
But one doesn't need to read anti-Mormon propaganda in order to be exposed to elements of Level B that can't quite be squared with an idealized portrait of the Restoration. Every maturing member of the Church will eventually discover that other Saints, including leaders, are fallible and sometimes even disappointing mortals. There are areas of ambiguity, even unresolved problems, in Church history; there have been disagreements about certain doctrines; some questions don't have immediately satisfying answers.
Dr. Kimball remarked that the Church isn't eager to expose its members to such problems. Why? Because souls can be and are lost on Level B. And, anyway, the Church isn't some sort of floating seminar in historiography. Regrettably, perhaps, most Latter-day Saints—many of them far better people than I—aren't deeply interested in history, and, more importantly, many other very important priorities demand attention, including training the youth and giving service. Were he in a leadership position, Kimball said, he would probably make the same decision.
But he argued that once members of the Church have been exposed to Level B, their best hope is to press on to the richer but more complicated version of history (or to the more realistic view of humanity) that is to be found on Level C. In fact, he said that, as a historian, he would love it if everybody were to reach Level C, which he regarded (and I concur) as far more nourishing and more deeply satisfying. Very importantly, he contended (and, again, I agree) that Level C—what I call the "synthesis"—turns out to be essentially, and profoundly, like Level A. The gospel is, in fact, true. Church leaders at all levels have, overwhelmingly, been good and sincere people, doing the best that they can with imperfect human materials (including themselves) under often very difficult circumstances.
But charity and context are all-important. Life would be much easier if we could find a church composed of perfect leaders and flawless members. Unfortunately, at least in my case, the glaringly obvious problem is that such a church would never admit me to membership.
The claims of the Restoration do, in fact, stand up to historical examination, although (very likely by divine design) their truth is not so indisputable as to compel acceptance—least of all from people disinclined to accept them. And people are lost on Level B.