Here is the Wkpda page and another paper. They says it's not been well researched. It says it is not overly helpful , though not harmful. Seems odd. It's huge.
Treatment and Education of Autistic and Related Communication Handicapped Children - Wikipedia
http://www2.uwstout.edu/content/lib/thesis/2003/2003peerenboomt.pdf
Treatment and Education of Autistic and Related Communication Handicapped Children - Wikipedia
http://www2.uwstout.edu/content/lib/thesis/2003/2003peerenboomt.pdf