One of the more defensible claims of
verbal plenary inspiration of
scripture is that the original,
autograph manuscripts (in their original languages) were, word for word, inspired directly by God.
Though a believer myself, I find such claims unsatisfactory, but not for the reason that some might expect.
If we are to believe that the authors of scripture were simply mouthpieces for God's wisdom, then how do we account for the unique marks of their written style in the old and new testament canon? In particular, if we are to discount the possibility that a book such as Jonah could be satirical rather than literal (as in fact it is!) haven't we lost some important part of the message of the book?
In the new testament as well, a strictly literal interpretation of Paul's epistles precludes the possibility for a wealth of spiritual wisdom that is to be gained from simply observing the attitude in which Paul addressed certain moral problems.
J.G. Machen is perhaps the best conservative scholar produced by evangelical Christianity in the last one hundred years (see the obituary that H.L. Mencken -- yes, Mencken! --wrote for him at his death). Machen's approach was to insist on a rigorous address to historical questions about the inspiration and canonicity of scripture, without discounting the possibility that even "errors" could be inspired.