Eddie, re: this:
“So what are the textual grounds for denying the miraculous elements in Jonah, and calling the whole story a parable … Are there crucial literary differences which justify treating the two accounts differently? I haven’t seen those literary differences shown.”
Perhaps you missed the URL I gave above, to my earlier comments on this subject in another thread here in the Biologos forums. See them at "Narrative Theology" approach to Scripture - #52 by dscottjorgenson …
Also see C.S. Lewis’ letter to Corbin Carnell, in Collected Letters Volume III The Collected Letters of C.S. Lewis, Volume 3: Narnia, Cambridge, and Joy ... - C. S. Lewis - Google Books …