Aussie Oz,
Although Rutherford is named in CTR's will only as a possible substitute on the Editorial Committee, Rutherford took control of the organisation through physical force and dubious legal manipulation.
Whereas the original organisation was democratic, Rutherford was adamant, while in prison awaiting the outcome of the voting, that he would never be held subject to the whims of the voting membership. We well know how Rutherford turned over the democratic process into his "theocracy".
It might be of interest to pursue the fates of the people who actually were named in CTR's will. When CTR died, the organisation broke up into innumerable splinter groups. An OCR of CTR's will is available at: http://www.jwstudies.com/WILL_AND_TESTAMENT_OF_CHARLES_TAZE_RUSSELL.pdf
As far as the SDAs are concerned, they were held to be on the outer of the 19th century Advent groups because they were under the control of a self-proclaimed prophet, and officially they did not keep on setting dates.
Doug