From my other entry I said:
I believe, from my research, that the absents of a Cross is an "accident" of history. Not that I don't think there were deliberate reasons - as the LDS Church has been using other symbols since almost the start. The Angel Moroni seemed to have replaced the Cross as a symbol because it represented many of the key teachings of the Church. It carries the Book of Mormon in one hand and a trumpet in another. This represents Restoration of the Gospel, calling of the Elect, Resurrection and Judgment, and etc. The Cross did not get added to the plethora of other symbols available for iconography.
To continue, what is missing is a discussion on the nature of “symbols” in Mormonism. When a symbol is used, what symbol and what kind? Mormons might not use the cross out of historical accidents and might make excuses to keep from starting, but why? I think it has to do with the sacred nature of symbol in Mormonism that is seen in few religions.
How has the Mormon use of symbols started? More often then not any significant symbol is associated with the Temple. There are only two “official” symbols used by the Church that are not tied to the Temple in a direct way and that is the Sacrament and the CTR ring. The Sacrament has a very specific purpose used at a very specific time. It is an extension of our baptismal oaths and covenants. One could argue that makes it partly Temple related. As for the CTR ring, it really started more as a primary gimmick that seems to have slipped from official usage and became consumerist. Paintings commissioned or displayed by the Church are actually rather generic and serving the purpose mostly of garnishing. There are still very few chapels that have any art (symbols) of any kind displayed - not even in the way of Islamic geometric patterns.
The reason Mormonism has not “taken up the cross” is because it already has a symbol that the cross fills in for; and that would be the Temple. Pictures of the Temple in homes are often placed where other religions would put their own symbols. When a prophet says that the symbol of Christ should be our own lives rather than a cross, that means something more than a cute expression of examples to others. That is precisely what the Temple is commanding us to do as members. Not saying that is what the prophets mean by that, but who knows? I have come to the conclusion that crosses are not bad (I prefer and keep, but don’t actually wear, an Ankh), but they are superfluous for Mormon tradition. I might even go so far as to say that Mormons who have gone to the Temple should put it aside. There might be several reasons a Mormon wants to wear a cross, but the only ones I feel that have a legitimate reason are converts and out of friendly gestures.
What I am about to say will have to suffice so that I don't step over sacred boundaries. When a person goes to the Temple they take on themselves more than the name of Christ, but make promises that they will become symbolically Christ in their lives. The life, death, and resurrection narratives are now part of our own narratives. Ultimately, Mormon usage of symbols is more than for memorial, but for transformation. Nothing in Mormonism is more important in that transformation than Temples where salvation is solidified by symbolic actions. The one piece of physical symbol taken out is not even to be shown. It is for this reason that I feel the cross and any other "Christ symbol" will remain outside of Mormon religious culture. There is no official need. If it was ever to be included it would be for political purposes.