A metaphysics for practical knowledge

Is Anscombean practical knowledge independent of what the agent actually does on an occasion? Failure to understand Anscombe's answer to this question is a major obstacle to appreciating the subtlety and plausibility of her view. I argue that Anscombe's answer is negative, and turns on the nature of mistakes in performance, and reveals a distinctive implicit metaphysics of mind and knowledge, structured by related capacities and exercises of capacities. If my interpretation is correct, then practical knowledge shares features with knowledge-how and knowledge-that, but deserves its own epistemic category.