I'm due to speak on Word and Spirit in Preaching at a minister's fraternal on Monday. Gordon Fee has some thought provoking things to say on this in his work on 1 Corinthians (New International Commentary on the New Testament, Eerdmans, 1987). In his concluding comments on chapter 2:1-5 he says,
"This paragraph has had an interesting history of application in the church, depending on where the emphasis has been placed. Some emphasise what Paul did not do, that is preach with excellence of word and wisdom, and glory in a more rough-hewn presentation (which interestingly enough, is often accompanied by a kind of bombast that seems intent on persuasion of a rhetorical kind, despite proofs to the contrary). Others wish to emphasise the "positive," the "proofs" of the Spirit's power, which they see as in contrast to preaching. On the other hand, the polished oratory sometimes heard in...pulpits, where the sermon itself seems to be the goal of what is said, makes one wonder whether the text has been heard at all. Paul's own point needs a fresh hearing. What he is rejecting is not preaching, not even persuasive preaching; rather, it is the real danger in all preaching - self reliance. The danger always lies in letting the form and content get in the way of what should be the single controlling concern: the gospel proclaimed through human weakness but accompanied by the powerful work of the Spirit so that lives are changed through a divine-human encounter. That is hard to teach in homiletics, but it still stands as the true need in genuinely Christian preaching." (p. 96-97)
The writer's God's Empowering Presence: The Holy Spirit in the Letters of Paul, (Hendrickson, 1995), is also very useful, especially his exegesis of the passage referred to above, and his treatment of the key text, 1 Thessalonians 1:5. It is not sufficient to argue for Spirit anointed preaching on the basis of historical anecdotes. We need to get to grips with Scripture, and Fee helps us to do just that.