I don't think that he meant to suggest any diminished mental capacities on his part. To the contrary, Louis Moore can produce a résumé of impressive accomplishments throughout his lifetime. Rather, when the former religion editor of The Houston Chronicle suggested that his newest book, Witness to the Truth, might be appropriately titled Forest Gump Goes to Church, he was referring to his uncanny tendency to have been a bystander at significant moments in the recent history of American Religion (especially American Christianity).
Moore has launched a new blog to go along with his new book. I have not read the book and have only read one post on the blog, but Moore has the credentials and the skills to make his contributions to both media worthy of your time.