Because the brain can grow new permanent connections between nerve cells , excersises that cause activity in the cerebellum part of the brain, will cause the cerebellum(a critical part of the brain) grow, and make all sorts of activity easier. People with ADD / dyslexia / etc. have a cerebellum that does not process sensory information from the 5 senses fast enough, compared to people without learning difficulties. the excercises fixes that permananently. The only problem with this approach is that it requires self discipline and a willingness to do , in order for it to have a chance to grow the cells required to fix the problem. many people just want shove the responsibility to the drug or doctor. I think the dore program is too expensive for what it does( checks the cerebellum and takes you through a series of excersises), compared to the other idea.
also you may wish to look up brain wave etrainment sound therapy. http://www.centerpointe.com/
I used this for about 3 months and found a huge shift towards clarity of thought and emotional control. It makes you irritable for a couple of weeks then it subsides. This one grows brain cells on connection between left and right side of brain, however this does not address the weak cerebellum problem and ADD specifically.
Please do youself a HUGE favor and stay away from chemicals and drugs. They can do nothing for you in the long term and they are an on-going cost..