Here's the process I went through.
Once I realized there was scientific evidence so support both settings, I looked at the origins of the respective theories. Both theories could find support in statements made by various people in the early days of the Church. But, once one recognizes that a hemispheric model doesn't fit the text, there were two specific and inconsistent threads.
1. The Mesoamerican thread relied on the unsigned 1842 Times and Seasons (T&S) articles and the so-called "Two Cumorah" theory.
2. The North American thread (commonly called "Heartlanders") relied on sections of the D&C, statements made by Joseph Smith, and letters written by Oliver Cowdery with Joseph's input, resulting in the so-called "One Cumorah" theory.
The Mesoamericanists concluded the 1842 T&S articles were the most credible because they were later in time and they were written by, edited by, or approved by Joseph Smith, whose views on the topic were evolving. According to several Mesoamericanists, the last word on this, supposedly, was the Matt Roper article.
The Heartlanders concluded the other sources were the most credible and discounted the 1842 T&S articles because no one knew who wrote them.
I read the Roper article and saw that Roper and his co-authors ignored their own data and announced that Joseph wrote or co-wrote the articles. I found that conclusion to be confirmation bias at its worst.
My next step was to examine the 1842 T&S for myself. I soon discovered that Benjamin Winchester was the primary author of the articles and that Joseph not only had nothing to do with them, he opposed them. I thought people would be happy to have the history clarified. I visited experts in the field. Generally, the historians and the Heartlanders thought the history was persuasive, but some Mesoamericanists resisted it. Consequently, I wrote The Lost City of Zarahemla so everyone could evaluate the historical data. Since then, I have discovered considerable additional material that substantiates my initial conclusions.
In my view, the foundation of the Mesoamerican theory now relies on the opinions of Orson Pratt, Benjamin Winchester, John E. Page, William Smith, and, to some extent, W.W. Phelps.
The foundation of the North American or Heartland theory relies on the statements of Joseph Smith, Oliver Cowdery, and the D&C.
In light of those respective foundations, I then went back to the evidence of historicity. This blog is partly a product of that process.
In the meantime, I observe that both Mesoamericanists and Heartlanders continue to include absolutes in their respective arguments; hopefully now we can all get past that.
In a few weeks we'll publish my book, Moroni's America, which offers a specific proposed Book of Mormon setting. I realize that, for some people, this will be just the 114th or 1 millionth "new" geography, but this one, really, is different. I have applied the methodology outlined by such authors as John Sorenson and Brant Gardner. I have rejected absolutes and focused on actual archaeology, anthropology, geology, and geography. I have considered linguistics, history, and other elements. I'm not saying it is the "final answer," and I welcome input, but I do think this approach satisfies the observation of Roger Terry on the masthead of this blog.
The more we exchange ideas about all of this, the better.
Hopefully all of this will accomplish my objective of having everyone interested in the historicity of the Book of Mormon reach a consensus.