JW doctrine on the face of it is reasonably simple but then when you begin to consider things like the sheer number of animals that would've had to have been on Noah's arc, or the logistics of an eternal paradise the apparently simple doctrine has to be continually adjusted and refined with ever more divine interventions and exceptions to the rules. In the end it becomes far simpler to accept scientific explanations and disregard the doctrine that creates endless and needless complexity when examined more closely.
Oh, yes but you're aren't really supposed to examine it closely now are you? They have answers for people who want to be told what to believe, not people who want to learn objectively. Any objective learning will lead to questions which simply can't be answered. JWs want to have the solution to every problem without any effort or work on their part.
New and contradictory explanations were frequent when it came to interpreting the Bible book of Revelation.
Yet JW's could not ignore them.
They had to teach these new and contradictory thoughts, whenever the latest book came out.
They do like to have it both ways don't they? They would say that these "deep things of God" have been made clear by Jehovah's holy spirit and the understanding keeps getting clearer. I would say the Revelation book really as a whole wasn't that complicated. It was basically just trying apply everything they could to the JW movement of the 1900s.
