John,
Your definition helps me to understand your question better. Yes, I have heard "expository preaching" defined in that manner, i.e., preaching through a book of the Bible or a chapter. I have always understood it to mean preaching a text in context, i.e., exposing the meaning and applying it whether it was one verse or several.
I would tend to agree that preaching through a book of the Bible
could help the congregation to understand how to read, study and interpret the Bible properly IF the expositor is faithful to the text... AND he also uses the "Analogy of Faith", i.e., comparing Scripture with Scripture so that no text is isolated from the whole of God's Word.
I also believe that there is a definite place and need for "Thematic/Topical Preaching". This is akin to Systematic Theology which takes the Bible as a whole in regard to what it teachings on a particular subject.
Thus, I could not give one method precedence over another and I certainly would not want to limit preaching to one to the exclusion of the other.

In His grace,