Hi,
I just read your post and there were a number of direct paralells with my situation. I have a daughter who is soon going to be eleven years old. She was never much of an eater (even while nursing) although for a few months I was able to manage to get her to eat a little chicken. That began and ended around age 2 - 21/2. Also at age 8 or so I made her sit at the table until she at that teaspoon sized piece of chicken. She gulped it down with some milk and threw it up. Milk, pasta, white rice, cereal, bread and the occassional green bean, red apple and potato are her diet. She does not like juice of any kind, nor does she like soda. She will, however condsume massive amounts of sugary foods. We have implemented the same suggestions that your doctor gave and it made no difference. She just went hungry and was not bothered by it - for a day and a half. I don't know what this is but I have been losing sleep over it for about ten years and I need help. Tried psychotherapy, occupational therapy, behavioral optomatry (don't ask me why) and several pediatricians. Have you found any answers? My daughter is going to be eleven and often get mistaken for a six or seven year old because she is so small now.
The idea of hypnosis was actually a sensible one, but a single visit will not suffice. Also, he should be sure there is nothing going on re: his metabolic and endocrine systems, so those areas should be checked out.