Not sure if we should focus on strengthening kids' weaknesses or capitalizing on their strengths. The facile answer is to do both, but there's a fundamental difference between these two approaches. I am thinking of Temple Grandin here. There are some weaknesses that cannot be "corrected" in us--many, I'd dare say. Do we waste time trying to teach a kid with ADHD to improve his organizational skills, or do we just buy him a smart phone and program a series of daily text alarms to help him remember things?
It's a hard question, and maybe it depends upon the weak area. If it's not a real disability, just a weak muscle, then sure, exercise and strengthen it. (For instance, I was never an athlete and couldn't run two blocks without getting winded, but with years of practice, I've become a competent runner able to complete a half-marathon in reasonable time.) But for kids with disabilities, how much time is wasted trying to correct something that is basically not correctable? Look at the case histories of kids with ADHD or Asperger's--their report cards show the same thing: "poor handwriting, inappropriate social functioning, needs improvement with organizational skills." We spend years telling these kids all the things they are doing wrong. What would it look like if we focused almost exclusively on what they did well, while providing some kind of support for overcoming the most egregious aspects of their disability? For instance, no one could make Temple Grandin develop emotional empathy for others, but they could teach her a specific set of rules for social interaction to follow even if she didn't really "get" them. She was finally liberated from her isolation when she was allowed to nurture her love of animals and run with this. She transformed the nature of animal husbandry in this country, making it a much more humane process for animals.
I am concerned that we spend too much of time as teachers and parents trying to make our students more similar to each other rather than deeply investing in their uniqueness and fostering it.