No offence, Downtown, but you are starting to sound a little like Jehoshua when he gets going about Roman Catholicism.
Why? Look, Jehoshua should be able to be picky about what gets to be called a Catholic and what doesn't. The Roman Catholic church has a centralized hierarchy that sets rules for membership. CHRISTIANDOM doesn't. There are some pretty broad themes (i.e believing in this whole Jesus fellow), but there isn't a single organization that sets themes for membership.
To the best of my knowledge, there are no groups that have splintered from the LDS church and continue to teach the Book of Mormon or believe in the idea that Joseph Smith was a prophet (which, along with the whole Jesus bit, are the central tenets of what separates Mormons from anybody else). The RLDS church, the largest offshoot, no longer teaches the BoM, has changed their name, and has forsaken their Mormon roots. If they wanted to call themselves Mormons, I guess that would be fine, but they don't.
The other groups are all tiny fringe groups that cling to the name only to thumb their noses at Salt Lake, and have virtually nothing in common with any characteristics that could be associated with Mormondom. You guys have to understand why we're so sensitive about this, given the incentives for so many groups (from political groups to religious conservatives) to push this MORMONS = POLYGAMY narrative, and given that these communities are often fraught with abuse, and wanton lawbreaking. People making that connection threatens the existence of the peaceful, law-abiding LDS church.
Imagine if there was a fringe group that broke away from the Catholic church, forsake the Pope, St.Peter, the Trinity, wantonly and openly abused children, and declared themselves Catholic. Can you see why people might be touchy and say "no you aren't?". Thats how we feel about polygamists.
ALSO, I'm not saying Kochman has to call Mormons Christians. I believe we are, but I am not disputing his categorization. I was only protesting his insistence that we still practice polygamy. We do not.