Scott,
The type of distinction you make is purely hypothetical. Regardless of what WCF maintains, while God is certainly “most free”, otherwise He is not God; God’s freedom to act does not mean He could have acted otherwise, potentially or not. He is omniscient and omnipotent therefore His acts are always perfect precluding any other possible action.
Tim

“God is also pure act(ion). He has no unactualized potential.”

Of course you mean ad intra (with respect to his being and perfections). Because if God was actus purus ad extra, then he would have done all things possible to his power, knowledge and will, but since he has not, those acts ad extra remain in potentia (i.e. unactualized potential). God is not only simple, but also “most free” WCF 2.1. His decree was free, though eternal and immutable. And if free, then he could have decreed other than he did. He left much potentia ad extra, only in potentia, not in actu.

Thanks Jeff.

See also Muller’s Dictionary of Latin and Greek Theological Terms. Pg.24: actus purus.