I meant narratively, not that his moral alignment is a physical prerequisite for accessing the True Power. You're right in that I don't think Rand being good would actually prevent him from using it if Shai'tan allowed, but the themes of the story are quite clear that using the Shadow's weapons against it is the wrong way.



There's nothing that would indicate that. The end of that confrontation indicates a change in Ba'alzamon's pattern of attack, not in the power of those attacks. If he had been using small balls of blackness and now suddenly had a large ball of blackness, I might agree. But as is, there is no indication that he was using the same power source (in fact, I get the impression that he was using Dreamwalking techniques more than either sort of Power in that battle. We've never seen anyone use Channelling to fill a room with water, for example, or altering air pressure, or gravity, and so forth). Besides, I wonder why you think it is more reasonable to claim Ishamael needed to beg Shai'tan to change the quantity of Power he was using, rather than to access it at all. We at least know that the latter is the general rule.