"Transactional Disability"; The Effect of "Situation" on Disability

I was extremely intrigued by Ira's post regarding this notion of "transactional" or "situational" disability. Considering the literal confines of a student's environment, and the ways in which this contained situation ultimately "defines" or "mandates" a given student's disabled/non-disabled status, is an important concept for each one of us to consider as future special educators. Ira contends that, if the physical characteristics or requirements of a classroom's context were to change, there is a high probability that a student's "disability status" could become altered as well. Take, for example, my older brother and his reading abilities--my brother was diagnosed with both Autism and mild cognitive impairments at a young age, and the physical act of "reading" is something that he still significantly struggles with. Now, it is not that his struggles lie in the comprehension of a given text, but rather, it is the actual, literal act of reading, deciphering, and decoding written output that he struggles with (more specifically, literacy aspects such as phonological and phonemic awareness, one-to-one word correspondence, rhyming, etc.). When text is provided to him orally (say, if I were to read to him, or if he were to listen to an audio-recorded text on our home computer), he would be able to comprehend much of the story's content. I would never contend or suggest that my brother is not Autistic, but, considering his ability to comprehend text when simple modifications were made, should his ability to decode and decipher individual words and phrases written or typed on a piece of paper been a component of his educational plan for all these years? If the "transactional" element of my brother's reading process was changed, I believe that the "characteristics" of his disability (in lack of a better term) would change as well. We then, as educators, must carefully consider the needs of each of our students, and be willing and able to modify the literal context of our classrooms to meet each student's specific academic and social needs.