A causal powers account of the favoring relation for reasons in a choice

Suppose we accept the following causal power account of what it means for reasons to enter deliberation:

1. A complex of reasons R counts as entering into a choice C in favor of an act of will A precisely when R confers on the agent a causal power to A as the outcome of C.

And suppose we also add:

2. In a choice C, there are two or more incompatible acts of will each of which is favored by its own complex of reasons entering C.

Finally, let’s add:

3. If you have a causal power to ϕ as the outcome of C, then it is causally possible for you to ϕ when you are in C.

It follows from 1-3 that:

4. In any choice, there are two or more causally possible incompatible acts of will.

And that’s a version of the Principle of Alternate Possibilities.

What about Frankfurt cases? Well, the above metaphysics of reasons gives a very nice response to non-theistic Frankfurt cases: No finite being can make you choose act of will A in C. For if someone did so, by (3), they would have to take away your causal power to will anything incompatible with A, and by (1), they would have to take out of the choice the complexes of reasons favoring acts of will incompatible with A, and in doing so they would thus be ensuring that by (2) there is no choice (but, rather, a shoo-in, where the reasons entering the deliberation end up favoring only one action).

What about theistic Frankfurt cases? Could God, without taking away the causal power for acts of will alternative to A, simply refuse to cooperate with such acts of will? Maybe. But I think in that case, he still wouldn't be making you choose A. At most, God could ensure you don't choose any alternative. But since you had a power for non-A, you wouldn't have to go for A. At the same time, you couldn't go for any alternative to A. Thus, I think, it would be possible for you to get into a position where you can't will contrary to A, but you can refrain from willing A. The only way God could take that away from you would be by taking a way the alternate powers, and in doing so he would be making you not make a choice.