For those who may be interested, I came across a couple of good books in the last year or two. The first one was Scribal Culture and the Making of the Hebrew Bible by Karel van der Toorn (2007), and the second was The Oral and the Written Gospel by Werner H. Kelber (1983). Both books go into the realities of the transmission of ideas in cultures where the vast majority of people cannot read or write, and they respectively consider how the "Old Testament" and the "New Testament" may have come into written form.
The principles and ideals of writing were vastly different in antiquity than they were in the 19th century, when the fundamentalist response to radical rationalism came into being. I no longer believe in verbatim inspiration of the Scriptures, though I believe God can use them as an objective base for teaching individuals the things He wants them to know.
I think Jesus' ministry was only a year or so long, mainly because I don't think he could have held the crowds at such a fever pitch for much longer than that without raising a rebellion against the Romans or crapping out (which, from an earthly point of view, he did).
I think there are many interesting things to learn by considering the similar incidents in the different gospels, especially thinking about why the incidents might have been recorded differently in the gospels' differing contexts, but I don't think a literal harmony is possible.
Love,
Steve