I recently read an article that pointed out some interesting patterns. In 1 and 2 Nephi, Isaiah and several themes related to his teachings are used extensively. Then, suddenly, Isaiah goes completely unused in Enos through Helaman (and the first part of 3 Nephi). Then, Isaiah is reintroduced “with a vengeance” in 3 Nephi by the Savior, almost as soon as He appears to the Nephites. Joe Spencer drew some interesting conclusions as to why that might be.