I posted all over the second link, so my views are pretty well represented there. One thing I learned in discussion there, though, is that there is a basic disconnect between polyamory and polygamy. The first refers to plural relationships that are voluntarily entered into and dissolved according to personal preference; it is up to the individuals involved to maintain the relationships as they see fit. The second involves marriage law, social convention, family pressure, and institutional support. It's a very different kind of animal.
Polyamory can clarify one point in the debate about polygamy: it can be possible to balance multiple partners without necessarily being cruel. That's just about the only relevance that polyamory, defined as a sexual choice among others, has for understanding what polygamy means in societies where it's practiced. To put it very bluntly: polyamory is about finding a niche in an open market, while polygamy is about finding the best refuge in a limited market.
The more interesting argument should address the in-between stages. Polygamy makes sense in certain economic situations, but what happens when cultural and legal traditions persist after the economic conditions have changed? The US strategy of crushing polygamy in the West will certainly not work in the more heterogeneous mideast--and I understand that Mohammed himself condoned and legalized polygamy.
So, am I crazy to think that these linked articles, all of which advocate polygamy against perceived opponents, might counter-intuitively be seen as progress? If woman-advocating-polygamy is seen as news, could it be that more news readers perceive polygamy to be a retrogressive institution?
Below the fold, I reproduce my ObWi comment on my family's polygamous history, with some preliminary remarks on Mormon theology.
The Mormon afterlife is extraordinally bureaucratic; certain forms can be processed in the afterlife, and others must be processed here on earth. (Baptism is one that must happen on earth; hence the genealogical work and baptisms for the dead.) The forms that are processed on earth then carry over into the afterlife.
If you get married to more than one person--even if the marriages were serially monogamous--you'll end up with a polygamous afterlife, according to Mormon theology.
Joseph Smith's capacity for underhandedness and, IMHO, chicanery, I certainly don't deny, but the practice became much more widespread (and better regulated) after the move to Utah, after Smith's death.
I tend to agree with you that the widows-and-orphans line reeks of apology and bull in the Mormon case. It's a line I've heard a fair amount from contemporary Mormons try to justify (here: "explain while condoning") polygamy. On the other hand, in some cases, it seems to have had some truth.
A rather long family anecdote, to illustrate the ambiguities.
My great-great grandmother was a very poor young woman from Germany. I'm not entirely sure whether she was on the East Coast or in Germany when she converted, but German was certain her first language. Either way, in the mid-to-late nineteenth century, once she converted, she would have had an established wagon train to get to Utah. Since at this time individual members' property was largely considered Church property (although the full communitarian attempt was mostly over), her migration would have been either heavily subsidized or free. She became Joseph Smith's grand-nephew's fifth wife.
Was she happy? I don't really know. Her son, from whom I'm descended, wasn't a believer and even ran away from Utah. His father found him, though, and brought him back to the fold. This son eventually chose to raise his children within the church, in his own way. There's a family anecdote about his refusing to give a personal testimony when on a mission.
Was she young? Yes, I think so. In the annual family newsletter from that branch, each of the wives is portrayed in a photograph--so that members can identify themselves by wife, macabrely enough. Her photograph is the youngest-looking of the lot, and she was pretty.
Was her fate as the fifth wife of a comparatively wealthy and important Mormon man better than what she might have faced as a poor immigrant in the East? It's really hard to say, but in the end, I can only trust that she made her choices as she saw fit.
(The father eventually became President of the Church after the Feds shut down polygamy in the US. For details of the continuing legal effort to prosecute polygamy, see this more general wiki entry. The family didn't break up, although some legal shuffling may have happened. Historical accounts I've read claim that he continued to perform polygamous marriages into the 20th century.)