The deeper you move into the Work, the more your choices reflect your True Will rather than the (subject to much distortion) personality "wants." In my experience, the more deeply you are in alignment with your True Will, the less likely your personality will make choices that are at odds with it.
You have infinite power to follow the path of True Will and to have everything necessary for that - the universe (i.e., Nuit) provides everything needed. But you don't necessarily have any power at all to do anything at odds with your True Will.
Crowley pointed out that by the time he became a Magus 9=2 A.'.A.'., there was almost nothing at all that he could do anymore except the ONE THING that was his to do - this aside from the fact that, years earlier as a G.D. 6=5 (roughly equivalent to A.'.A.'. 2=9 or a little higher) he could do miracles almost on demand. The difference is that, as the whole of his manifest being became more tightly aligned with the central pulse or stream of his being, there was no power "leaking" into other things.
James Eshelman ~ T.O.T.
