cured doesn't enter into the equation. It's whether the person is sane at some point and as such can be held accountable. If the person relapses, then its back to where they were.
as to the bound term: that is not whether they understand whether somebody hurt them. Its whether they understand they hurt somebody else. If they were harmed, others can stand in for them. Whether it be the state, in a criminal trial or a guardian in a civil situation, the injured party is represented by another party. It is when the injuring party cannot understand their rights that it becomes an issue. If one cannot comprehend their rights or cannot assist in their own defense, it is improper to prosecute them. They would not be able to understand their rights.