KC Kern did a series of guest posts at Wheat and Tares called “Legend of the Lost Book of Gold”.  I thought he did a fantastic job discussing the theory.  In part 1, he discussed a story of Christian missionaries taught a group called the Karens that already worshiped a god called Y’wa.  Part 2 discusses the actual theory in more depth.  Part 3 discusses common objections to the theory, and Part 4 gives a conclusion to the series.  If you haven’t read the series, please check it out.