As to Lutheran theologians from the Age of Orthodoxy:
“Scholastics” is something of a pejorative term in the history of Lutheran theology… That being said: Yes, there is plenty of discussion amongst Lutheran dogmaticians down the ages who have affirmed and discussed what the limited, natural knowledge of God is. And it is a live discussion. I and my comrades certainly affirm Paul in Romans 1:20, but I (and others in my tradition) do not think it opens to door to a Christian use for the scientific investigation of ID. If for no other reason than because it sounds awfully scholastic (that is, overly speculative). My description of our theological history is hardly flawless or full! But I’m interested in what your sources are on the subject? Always fun when non-Lutherans know that Lutherans exist!
As to the argument about the diminishing of God, I’m sensing some internal influence on my part from William Placher’s The Domestication of Transcendence. Sadly, his book is not on me at the time. Something about modernity and its ability to put God in a box. I have no doubt theologians (professional and lay alike) from every body, movement, and creed are tempted to domesticate and diminish transcendence; EC and ID, no less. My argument was that there is, in fact, a risk of it in ID (something I don’t think you’d discount). I’ll leave it there as I agree with Dr. S. This isn’t the place and I frankly haven’t the time to flesh out each thought. Advent/Christmas-tide are busy times at a church, as you can imagine! (Convenient excuse, eh?)
As to Luther, however; I quote:
”Men see that the heavens and the earth are so wisely governed and then, on the basis of this external government and the nature of creation, they draw the weak conclusion that there is one God… Such a knowledge of God, which is based merely on the fact that the earth remains and the heaven does not fall down, is weak and superficial.” (WA 45, 90; Luther quoted from Oswald Bayer’s The Theology of Martin Luther, page 17, footnote 11)
He is for a type of natural knowledge of God and affirms the reality that some characteristics of God can be sensed, somehow, by humanity in nature; his power and divine otherness. But this knowledge is always weak and superficial. You rightly point out it cannot give knowledge of salvation. But what Luther adds to this is that any knowledge of God given in creation is not certain. One must then ask what sort of claims ID (as you being a Christian, and those you align with, see it) makes. Is it your assertion that ID is seeking a weak and superficial knowledge of God? If so, then yes, you and Luther are not so far apart. And if your skepticism on the subject is as pervasive as mine, then we are not so far apart either!