As much as sex is discussed as it relates to polygamy, do you really believe that BY and HCK had the sexual "means" (time,energy) to satisfy all their wives?
This is the only part that I see as working out pretty good, at least for Brother Brigham. It's a part of our evolution to desire multiple sexual partners. I see myself as a normal male and I know my own feelings and experience on what the natural man desires. I can't speak for all men. Heck, some men desire other men, which I'll never understand. But I'm willing to bet that most men have the same desires that I do, even if they won't admit it out of political correctness.
I agree that 50 is a stretch. But given male and female sex drives being the way I see it. I could see a 4:1 female to male ratio working out for a pretty good rotation. But even 4 would get old after a while and you'd just want more and more. My point is that the bodies and minds of modern men (humans for that matter) are not perfectly fit to our environment. Evolution doesn't select for happiness, just viability. This is why we have remained this way for so long, and why I don't see it changing any time soon.
Perhaps Joseph Smith was looking for a solution to this problem, and drew upon the scriptures for guidance. But this is difficult for me to accept given the demand of absolute celibacy for boys and young men. If you can make it through that and not give in, any other self mastery challenges are a breeze. So I don't think it's completely to say it was just dirty old men, especially if these men were able to remain celibate as boys.
Now I fully admit that this is a male problem and a man's desire for happiness tramples a womans rights if she is coerced into a polygamous relationship. But I think women have a similar problem. They've evolved to accept nothing less than the very best man, the alpha man. Women are very picky about who they mate with. If you ranked 50 men in order of desirability and 50 women in order of desirability and then tried to pair them up, #1 with #1, #25 with #25 etc. I contend that it would be the women who would feel like they were getting a bad deal and not the men. This is a consequence of our polygamous ancestry.
Granted, she would also like to have the alpha male all to herself. But this is no more possible than for a man to have an infinite number of wives all to himself. There can only be one "worthy" man, or at least only a few. And don't think that evolution has shaped in women the desire to be loyal to each other in that they would respect that this man belongs to another woman. Granted some women may repress or control this desire, but I've seen enough unscrupulous women to know what the base human desire is. These base desires are always there and we fight against them every day, just like the desire to over eat. No matter how righteous or how noble you think you have become. You're still human.
So men and women could both ask. Why did God give us these desires, if we can never fulfill them? Can we ever be truly happy or is happiness just a momentary sensation? On earth I think happiness is clearly a transitory thing. Perpetual and lasting happiness would have to come in some other world.
And when the confederates saw Jackson standing fearless as a stone wall the army of Northern Virginia took courage and drove the federal army off their land.