Adam-God theory was never stated by the Church. The misinterpretations are typically the misinterpretations of people who are not LDS. Brigham Young’s comments are not understood well by those who claim Adam-God theory. To better understand BY’s statements you need to remember that some terms are used as titles. He uses Adam interchangeably with God the Father and Adam the man. He also uses God as a term referencing the role of Adam as judge over all mankind.
Journal of Discourses 1 pg 50-51
[Adam] is Michael, the Arch-angel, the Ancient of Days! about whom holy men have written and spoken - He is our Father and our God, and the only God with whom We have to do. Every man upon the earth, professing Christians or non-professing, must hear it, and will know it sooner or later … When the Virgin Mary conceived the child Jesus, the Father had begotten him in his own likeness. He was not begotten by the Holy Ghost. And who is the Father? He is the first of the human family; and when he took a tabernacle, it was begotten by his Father in heaven, after the same manner as the tabernacles of Cain, Abel, and the rest of the sons and daughters of Adam and Eve; from the fruits of the earth, the first earthly tabenacles were originated by the Father, and so on in succession.
Most commonly people do not read the entire statement, the bold is mine. How could Adam, the first of the human family, be his own father? This section specifically states that Adam’s father was his Father in heaven. It states that Christ was literally the physical offspring of Heavenly Father, in the same manner that Cain, Abel and the rest of the sons and daughters of Adam and Eve.
Now, I am not entirely positive what BY meant earlier in the statement where he states “[Adam] is our Father and our God, and the only God with whom we have to do.” However, given the typical response of LDS critics stating that “gods” references “judges” combined with the LDS belief that Adam will sit as a judge over all Man, logic leads me to believe that Adam is the Father of all Man and is the judge of all mankind. This follows similar to the statement that the original 12 apostles will judge Israel.
Given that the statement of Adam being our Father and God and the statement that Adam’s father is his Father in heaven are conflicting, it is an error to assume that BY was stating that Adam was God the Father.