#1...If Woodruff's 1890 declaration had taken amongst all of its leader, the 1904 Second Manifesto would have been redundant/superflous.
#2...May I suggest you at least look at the lengthy appendix in Solemn Covenant: THE MORMON POLYGAMOUS PASSAGE (and perhaps read a chapter or two from this book)
Hardy, himself a descendent of polygamists, lists (if I recall correctly) about 260 plural unions between 1890-1910 in the appendix. These were solemnized by hierarchy Mormons.
If you look at this list closely, you'll see some of these additional plural unions lasted all the way until the early 1960s.
#3 To elaborate further on this, Woodruff's declaration didn't evaporate most of the existing plural unions as of that time.
#4 Current Lds teaching is that if you are solemnized to more than one spouse in the lds temple (for example, a second after the first died), you are a polygamist as of death...provided you make it to the Celestial Kingdom, that is.
#5...Lds "apostle" McConkie taught that polygamy was a "holy practice" that would jumpstart again when the Mormon jesus returns...(see his book, Mormon Doctrine).
The reason I posted Woodruff’s 1890 declaration was in support of another poster’s claim about a 19th century declaration against polygamy. In no way was I making any claims as to the effectiveness of said declaration, only that it existed.