To help my google group's discussion about physical therapy and exercising both side at once, I did a "google" hoping to find information.
Dr Hooshmand in his section P.T. and CRPS Part 1 writes
"Anytime the patient is doing physical therapy or hydrotherapy, all the activities should be on both sides. The patient should not apply the treatment only on the side of the body that is painful. The main reason being that the nerves for temperature control of the body start from the central nervous system and go all the way down to the spinal cord. So, if the patient has a lateralized pain, spasm, or limitation of motion, the exercises should be done on both sides, otherwise there would be a temperature asymmetry causing improvement to temperature on one side at the expense of the other side becoming colder. This type of bilateral exercise also prevents spread of CRPS."
If you're reading this and you have any other information supporting this please comment and let me know. I was able to find information about acupuncture used bilaterally to help for pediatric CRPS.