Emy,
In 1959, they changed from believing the higher powers of Romans 13 were the governments to believing it was Jehovah and Jesus. They even called the previous belief a "false doctrine". (1) Just four years later in 1963, they changed it back again to what they believed before 1959 (2). I believe there were changes back and forth before this, but I don't have the references. Someone who has the old literature on CD may be able to find these.
They also contradict their "tacking" analogy. "It is a serious matter to represent God and Christ in one way, then find that our understanding of the major teachings and fundamental doctrines of the Scriptures was in error, and then after that, to go back to the very doctrine that by years of study, we had thoroughly determined to be in error. Christiians cannot be vacillating - 'wishy-washy' - about such fundamental teaching. What confidence can one put on the sincerity of judgement of such persons."
1. Jehovah's Witnesses in the Divine Purpose, 1959, p. 91.
2. Babylon the Great Has Fallen, 1963, p. 548.
3. The Watchtower, May 15, 1976, p. 298.