I can understand why they changed the definitions, because both conditions have the same root cause (an issue with sensory processing) but I think it was a mistake. You've got a completely different presentation, and completely different treatments. So now any research into developing new therapies for autism will have to specify which subset of Autism spectrum disorder they are targeting, subsets which may not be well defined or consistent. I think eventually they will carve out sub-categories of autism based on which therapies they best respond to.