Proof of Divine Simplicity?

Dear Dr. Craig,
Concerning your take on God's existence and analogy in Question 276, the Thomistic philosopher and blogger Alfredo Watkins has responded to you here: http://analyticscholastic.blogspot.com/2012/07/william-lane-craig-on-god-and-analogy.html .
I am particularly curious as to your thoughts on his argument for divine simplicity, which entails that talk about God must employ analogy. He gives the following argument:
(1) Whatever is non-identical to God is created by God. [conceded by Craig]
(2) If God has metaphysical proper parts ('parts' hereafter), then at least one of these parts is not created by God. [prem]
(3) Either God has parts or he doesn't. [LEM]
(4) Suppose he does have parts. [assp]
Then
(5) All of God's parts are created by God. [by 1]
But
(6) One of God's parts is not created by God [by 2,4]
This is a contradiction. Hence, we must reject our assumption. Hence:
(7) God has no parts.
So by 'metaphysical proper parts' here I mean things like ontological constituents, such as a property-instance (or trope or accident or whatever). (1) is just Craig's own thoughts on the matter, and (2) is true because clearly God doesn't create his essential properties; he depends on those for his existence, since if they didn't exist then neither would he. The rest follows by the meanings of the terms and the rules of logic.
Craig says that he considers God to be a substance, presumably in the same manner we are: "Not a physical substance, of course, but a spiritual substance like a mind."
However, the case is even more clear if Craig thinks God's mind and will are distinct; for if he does, granting Craig's doctrine of aseity, then from (1) it follows God's will must be created by God. But it is absurd to suppose God creates his own will; after all, he must have a will to do that! So, either Craig's doctrine of aseity is false (which I agree with Craig it isn't) or God is not distinct from his will (which I think is right, but is really only intelligible given divine simplicity).
Craig thinks getting rid of Platonism will solve the problems concerning God's aseity; but it doesn't, since even if there are no abstract properties in us there are clearly ontological constituents (my brownness, my height, my shape, etc.). Even taking 'parts' in this sense, I think the above argument shows that if he wants to hold on to the strong doctrine of aseity set out in the quote above he needs to get rid of the idea that God has any parts at all. And if God has no parts in the metaphysical sense then it can be shown speech about God is analogical; for in our case, to say I am good is to say the quality of goodness inheres in me as an accident (or is exemplified as a property, or inheres as a trope or whatever). But since God has no parts in any of these senses, to say God is good cannot be to say this about him. And the same with any of the divine attributes. Thus our terms must be said analogically of God."
It's also worth mentioning that Alex Pruss has offered a simpler version of this argument, which I have adapted as follows:
1. Everything other than God himself is created by God. (Premise)
2. If God has metaphysically proper parts, then at least one metaphysically proper part of God is not created by God. (Premise)
3. No metaphysically proper part of God is identical with God. (By definition of "metaphysically proper part".)
4. If God has metaphysically proper parts, then there is something that is neither identical with God nor created by God. (By 2 and 3)
5. God has no metaphysically proper parts. (By 1 and 4)
Do you think that Watkins' or Pruss's arguments are good ones? If so, do they prove divine simplicity as conceived by Aquinas? I myself have been very wary of the Thomistic conception of divine simplicity given that it entails that God is timeless, immutable, and impassible, so any insight you might have on these arguments would be greatly appreciated.
Thanks,
Pranav
United States


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