JFS teaches that MIH was revealed to the Church, not through ERS, but JS, and is a revealed doctrine of the Church.
Joseph F. Smith, "Discourse Delivered at the Oneida Stake Conference, Franklin, Idaho, Sunday Afternoon, January 20th, 1895," Deseret Evening News (Feb. 9, 1895): 9
Our Heavenly Father has never yet to my knowledge revealed to this Church any great principle through a woman. Now, sisters, do not cast me off nor deny the faith, because I tell you that God has never revealed any great and essential truth for the guidance of the Latter-day Saints through any woman. "Oh! but," says one, "what about Eliza Snow's beautiful hymn, 'O my Father, Thou that dwellest,' etc? Did not the Lord reveal through her that great and glorious principle that we have a mother as well as a father in heaven? No. God revealed that principle to Joseph Smith; Joseph Smith revealed it to Eliza Snow Smith, his wife; and Eliza Snow was inspired, being a poet, to put it into verse. If we give anybody on earth credit for that, we give it to the Prophet Joseph Smith. But first of all we give it to God, who revealed it to His servant the Prophet. God reveals Himself and His truths through the channels of the Priesthood.