Your examples attempt to break the chain of "aboutness" between meta-levels of statements. But there's a crucial distinction your argument misses:
"Nothing true can be said about God from a posture of defense" isn't merely describing properties of statements like your examples do (word counts, colors). Instead, it's making a universal claim about POSSIBILITY itself, specifically, the impossibility of defensive true statements about God.
This raises a key question: What makes defensive truth claims about God impossible? This impossibility must stem from something about God's nature itself. Otherwise, what grounds the impossibility?
Your examples all involve contingent properties:
1) Book word counts are contingent features of books
2) color(X) = color(Y) involves contingent properties of objects
But the original statement makes a necessary claim about what kinds of truth claims about God are possible at all. This is fundamentally different because:
1) It rules out ALL possible defensive true statements about God 2) The basis for this universal impossibility must lie in God's nature 3) Therefore it necessarily makes a claim about God, not just about statements
This is why property inheritance examples don't apply here. The statement isn't claiming properties transfer between levels, it's making a universal claim about possibility itself that necessarily involves both statements about God AND God's nature.
While you've shown that descriptive properties don't transfer between meta-levels, this doesn't address the key issue: a claim about what statements about God are possible must ultimately be grounded in God's nature itself.
> a claim about what statements about God are possible must ultimately be grounded in God's nature itself
Ah, so you're saying that the original statement "Nothing true can be said about God from a posture of defense" (call this statement "O") is self-defeating not because it applies to itself, but because it applies to one of its (lower-order) premises (call it "P"), which is itself about God? This is different than your original argument "The statement itself is a claim about God" but we can go with this as well.
I think your new argument relies on that premise P being made "from a posture of defense," otherwise O doesn't apply. I don't see any evidence of this being the case, so I don't think your argument is correct.
In other words, two conditions need to be satisifed for P to apply to a given assertion:
1) The statement must be about God.
2) The statement must be made from a posture of defense.
P doesn't satisfy (1) and O doesn't (have to) satisfy (2). Am I wrong, or what am I missing here?