I largely agree with Kaimi’s thoughts on how the Church is usually content to let teachings and statements of earlier authorities fade into obsolescence through silence, rather than through any kind of formal pronouncement. But I think that the opposite, that the silent treatment is intended as an informal repudiation, might not be true in all cases. I don’t think that any general authority will provide a clear answer on nineteenth-century polygamy any time soon, but I don’t think their silence will provide any guidance, either.
Personally, I believe that polygamy was instituted and abolished according to divine will, although its beginning and end appear to have had some rough patches. I’m happy polygamy is gone and don’t expect it to come back, but I honor and respect the sacrifices made by my great-great-grandparents. I’d guess most members of the Church share a similar outlook, and I’m also consciously projecting my opinion onto the current general authorities. I strongly doubt any of them would in practice clearly affirm the practice of polygamy up to 1890, however, because clarifying what is mostly a matter of historical curiosity would come at the price of encouraging present-day polygamists who are relatively few in number but highly visible from Salt Lake City and in the national media.
I don’t want to exaggerate the effect of the audience on general authorities’ sermons, but I suspect that they usually try to counter-balance rather than amplify what they see as negative influences. The message already comes through loud and clear from other quarters, for example, that wealth and professional accomplishment are what matters most; the general authorities will spend most of their time pushing back against that idea, not reinforcing it, even if the Church as a whole is fairly supportive of economic advancement and secular honors.
There are a couple of problems with this approach to apostolic silence. I’m not saying, for example, that the Church teaches strict chastity outside of marriage, while the world teaches licentiousness, so therefore the truth must lie somewhere in the middle (“itâ€™s OK if you’re at least 21 and really, really in love”). I also have a vigorous dislike for the notion of deep, secret, or untaught doctrines. I wouldn’t want this approach to polygamy to provide a model for rehabilitating nineteenth-century statements that have been intentionally left behind. I merely suggest that in the case of nineteenth-century Mormon polygamy, current historical circumstance makes me reluctant to conclude what I otherwise might from the long silence of Church leaders.