Bill, from what I could gather, provided two personal reasons for why Mormonism has been beneficial to him:
1) It's a crucible against which he was able to further develop as a human being
2) The community provides a feeling of safety and security, both materially and spiritually (for lack of a better word)
He then makes the argument, and this is my summary, that these same benefits still exist for others and that his role is to help shepherd them through the process. As far as developing as a human being, he explicitly mentions the ability to recognize one's own authority as equal or superior to the church's institutional authority. Both these ideas are very close to Fowler's definition of a transition away from Stage 3, through 4, and into 5. However, the sticking point of safety and the nagging feelings of self doubt, maybe stemming from a time in adolescence when he felt he was on the wrong path, has resulted in a sticking in place passed the time one may have already moved on. Because the LDS church is a stage 3 religion, and for it to move into a different stage would require much more than a few tweaks to doctrine. It would require a paradigm shift en masse equivalent to the personal shift many of us have experienced within ourselves.
Fowler refers to Stage 3 as an adolescent phenomenon because its at that time that this type of "faith" (I think worldview is a better word) is developed. We see others seeing us and become aware that they can perceive us in a way that is different than how we perceive ourselves. We begin to seek out role models and authority figures for the purpose of finding acceptance and doing "the right" things. This is what really makes Mormonism relevant for many people who have a difficult time navigating or finding acceptance and identity in the world. And as the danger for becoming dependent on the "tyranny of the they", this is a stage that many people never leave and remain in for the rest of their lives.Stages of Faith, Chapter 18. Stage 3 Synthetic-Conventional Faith wrote: ...in the interpersonal world of Stage 3 faith their expectations help us focus ourselves and assemble our commitments to values, but there is always the danger of becoming permanently dependent upon and subject to what Sharon Parks calls the "tyranny of the they." For Stage 3, with its beginnings in adolescence, authority is located externally to the self. It resides in the interpersonally available "they" or in the certified incumbents of leadership roles in institutions. This is not to deny that adolescents make choices or that they develop strong feelings and commitments regarding their values and behavioral norms. It is to say, however, that despite their genuine feelings of having made choices and commitments, a truer reading is that their values and self-images, mediated by the significant others in their lives, have largely chosen them. And in their (the youths') choosing they have, in the main, clarified and ratified those images and values which have chosen them.
I conceive a Stage 3 religious community like a group which automatically accepts all comers, which is attractive, as long as they are willing and able to conform to specific requirements. By conforming to an authority and accepting a collection of "right answers" and "right living", you gain access to an extended family. Stage 3 relationships are therefore defined by how well an individual is able to conform to the checklist. If one person is able to rattle off a list of beliefs and practices, and then sees that your list of beliefs and practices match, then the bonding is instant. This faith stage is un-reflective of itself, meaning that you don't reflect on why particular items are on the list and others are not, because that isn't the point. The point is to conform to the list and then connect to others doing the same thing. Reflecting on the contents and there reasons is seen as alien and strange. At worst, its seen as blasphemous because those questions are and must forever remain unknown. To reflect on those things would bring about the disturbances of Stage 4, and what we usually associate with a faith transition.
If you look at what Bill describes in his own life, then he says that Mormonism worked for him between the ages of 17 and 27. Fowler indicates that Stage 3 usually encompasses the ages of 13 to 18. Stage 4 is most commonly found in a person's 20's, and Stage 5 in a person's 30's. While it is certainly true that many people within Mormonism make these faith transitions and remain active, they continue to do so without upsetting the Stage 3 nature of the religion itself. It is authoritarian, unreflective, and obsessed with providing models for conformity. In contrast, a Stage 5 religion would be like what you would find in a Unitarian Universalist congregation. A person who has made a transition, or is in the process of doing so, may find a way to remain within the church but the organization is never going to provide the type of environment they'd prefer or even flourish with. Questions and doubts are viewed as evil and disruptive to the Stage 3 project, and anyone promoting non-conformity is essentially attacking the very foundation of what the faith is constructed on. From this perspective, one could pose this hypothetical: "How long would it take for Mormonism to evolve into the type of church embodied by Unitarian Univerasalism?" Will remaining within Mormonism, in any way, push the church in that direction?
I think the answers to these questions are: "Probably a lot longer than me or my children will be a live" and "No". What we're looking for in a religion or a community are not minor tweaks, they are massive and difficult shifts in perspective and worldview. We can, for example, become indignant that our black and white television won't display color, then continue to watch it anyway while grumbling and shouting, but our angst won't make a damned bit of difference. The damn thing won't display color because that ability doesn't exist within its structure. If you want color, then you need a new television.