I don't understand why people insist that the Trinity doctrine is what makes a religion Christian. Mormons believe that it is only through the atonement of Jesus Christ that all mankind may be saved. Isn't *that* what makes a person Christian?
I don't think Shavano is saying that merely calling oneself "Christian" is sufficient; instead, he is saying that calling oneself a worshipper of Christ is sufficient. He is not rendering the term "Christian" meaningless, he is just defining it differently than you apparently define it.
We Mormons believe that both Jesus Christ and his Father are God (or gods, if you prefer), and that Jesus Christ is the literal son of the Father; in addition, we believe that they each have physical, tangible bodies of flesh and bone. (People who believe in the Trinity must necessarily believe that there is at least one physical body involved, because Christ had one after his resurrection, so believing that the Father has one too should not seem too much of a stretch.)
The *actual* difference between our belief and the Trinity doctrine is that we do not include a self-contradictory assertion that they are somehow both separate beings and the same being at once. Instead, we believe that the Father and the Son are separate beings who are one in purpose, that is, they work together in perfect unity. (This has the added benefits of being logically self-consistent, and of not contradicting anything Christ said during his ministry; I can give examples if you wish, but perhaps that would be best done via e-mail so as not to take this thread too far off topic.)
But the real question is, why does believing one or the other affect whether one is Christian? In practice, both beliefs lead to the same basic behavior: we worship the Father in the name of Christ, and believe that through Christ's atonement we can return to live in their presence.
Can you articulate exactly why it matters whether they are the same being and yet not the same being, or whether they are two beings (Father and Son) who are perfectly united in purpose? Why, exactly, does my belief disqualify me in your eyes from being Christian, despite the fact that I believe Christ is the only path to salvation? (This is a serious question; I've never gotten a response to it other than "it just matters!".)
(For the sake of simplicity I omitted the Holy Ghost from my above comments. The Holy Ghost is included in the standard view of the Trinity; Mormons consider the Holy Ghost a third, separate personage of spirit, who does not possess a physical body as the other two do. In either case, the Holy Ghost serves the same function. However, I do not think this is particularly relevant to the discussion at hand.)