I will say this... immediately I got the impression that they can solve all disabilities with some "elbow grease" as it were. Perhaps by the same token a hammer will help dandelions grow because it's been proven to work on nails.
There are some aspects to a disability that cannot improve with "exercises" and some can get worse. One case in point is my sensitivities to certain sounds. I cannot desensitize myself. Another example might be sexual preference. While it's true that behaviours can be blocked, one cannot take away a person's preferences regardless. (And inhibiting and not fulfilling those needs can cause much stress in life to the point of feeling effects of starvation and unfortunately, gaining weight... which can become a vicious cycle.)
There are exercises that can be used for coping and there can be some things which are "grey" between "is the disability" and "is the lack of effort" but in either case, recognition of the disability is needed and understanding one's limitations is required in order to be able to progress on any "progressive" kind of work. In a make or break situation, nature will just take its course and repercussions can happen and dealt with sometimes. It is tragic when systematically, people are put in positions of dire make or break situations with known limitations and it isn't quite fair. The expectations need to be there and constant encouragement need to be there and not a lot of "blame" for "the past".