I'm glad you're son has had such a positive response to dietry intervention.
I don't know anything about Chelaton Therapy.
My son has been trying dietry intervention for about 4/5 months GF/CF. He also takes fish oils, magnesium, B Vits and Probiotics.
I started him on the diet because I have Fibromyalgia and I am feeling alot better on GF/CF diet, alot of my symptoms are lessening. I also had alot of sensory symptoms, although I am not autistic.
I think there must be many routes to autism, simply because different therapies have a positive effect on some children, but no response with others.
I find it a real pity that on some websites there is an almost fanatical approach either for or against interventions.
An adult with autism can make the choice for themselves if they wish to try interventions. And I think we have to respect those who just want to be accepted as they are. These are usually at the higher functioning end, and who can blame them everyone needs to respect anothers choice.
My paediatrician (and other professionals) said that the dietry intervention was only worth trying if he was showing severe behavioural problems. Which he isn't.
But because of my condition and a family history of dairy intolerance and genetic differences ie. hemochromatosis etc I decided to give it a go.
I haven't noticed a huge difference. But I think it takes over a year for gluten to get out of the system. He does seem a little spaced out. But even if he has similar symptoms to me, and the diet improves that, I still know that he is autistic and will need to keep to this diet for the rest of his life.
My son is 7 years old. He has a severe speech disorder. His understanding of receptive speech is at around 3 years. However he also has alot of sensory issues and maybe auditory problems are contributing to that. His expressive language is classed as normal. However he uses delayed echolalia from TV and DVDs, so he can use quite elaborate language, but he is putting his speech together like pieces of a jigsaw puzzle from phrases he has already heard. So it can give a false impression of his understanding.
He tends to be passive, not initiate social interaction. Although, if asked, he will play with others quite happily. He doesn't always manage to follow others imaginary play. Sometimes he can be totally unaware of everyone and everything around him.
He doesn't have any rigid routines or obsessions. He used to have problems with transitions, but that is much better. He doesn't appear to me to have a narrow range of interests. But he does have problems paying attention to anything he is not interested in. But I think he has most difficulty at school. Autism seems to have particularly affected him academically. He has trouble remembering letters/words/numbers out of their sequential place. For example, if I put ten letter cards on the table and I ask him to point to the letter 'b', he could do that. So he recognises it visually. But if I were to just pick up the letter 'b' and ask him "what letter is this", he cannot do it. So somewhere the communication between visual and verbal recognition is lost. He may also have dyslexia. He tends to write the mirror image of things ie. if I hold his work up to a mirror I can read it. I have just found out that he doesn't have binocular vision after a routine trip to the opticians. So he is seeing double vision close up.
Executive Functions: these are usually higher level brain skills. Difficulties you would begin to notice from school age upwards. It is things like being able to plan ie. If he was going to make a model would he be able to get everything together to complete the task. To sequence ie. does he understand the natural progression of how to complete a physical or mental task or would he put the steps in the wrong order or miss out some of the steps. Being able to organise yourself (aspects of planning and sequencing). Understanding 'time' ie. without an understanding of time you are unable to understand any concept requiring this understanding. Children may not understand yesterday, today, tomorrow. Trying to explain the past, present and future would not make sense to them. These children tend to function very much in 'the now' or on 'this day'. It will affect school work because you need to understand how long you are given to complete the essey, topic, exam etc.
I am just at the point of finding out if my son will get a Statement of Special Educational Needs. If he does then I will try to move him to a mainstream school that also have extra provision for those on the spectrum. He is presently at mainstream school, but the staff have very little understanding of his difficulties. He is making progress, but it is very slow. He is about two years behind his peers academically and I can see that gap getting wider.
He is interested in lego, puzzles, model building, electronic gadgets and how they work. He is a very kinesthetic learner.
I have seen on other web discussions people talking about getting positive blood tests back. As far as I have been told in the UK there is no test that can be done to say 100% if your child has food intolerances. Anything involving needs or skin prick tests are out of the question for my son. I have had his urine tested and that came back positive for peptides from gluten and casein. But again the professionals tell me that the presence of those peptides doesn't prove anything because they can also be present in NT population as well.
Someone else sent me information about the Marshall Protocol for Fibromyalgia and Autism. It sounds very interesting and I have forwarded the info to my nutricianist. But again no real proof of its relevance to FM and ASD. It also sounds a very long and invasive procedure.
But all we can do as mothers is try our best at things we think are relevant.

I forgot another executive function. That is predicting outcomes. Obviously we adjust ourselves depending on our understanding of the future outcome. If we are unable to see the end product of what we are doing/saying/thinking life is going to be very difficult and confusing.

Well I wouldn't use the word cure.... but recovery is pretty accurate. I can take my son off of his supplements and fill his diet up with junk food high in processed items with artificial colors, flavors, sugars etc and watch him backslide slowly. There is a lot of stuff going on in these kids bodies that affect them neurologically and if you treat the body well the mind responds too. :) It's like an alcoholic - you are never be cured of your alcoholism but you can be in recovery by controlling what you put in your body.

Anyway we continue or journey of treatment and things just keep getting better. I know some people are skeptical, and some try one or two things and don't see much benifit so they dismiss bio-med, but all I can say is it is worth trying everything you can (it is safe!) because you just never know what will help. I know SO many families on the spectrum and they all have differering experiences on what works, but at the end of the day the vast majority see at least some degree of improvement, and many see a very large improvements.

I was just a guest speaker on a panel of parents of recovering kids at an autism conference in phoenix- we all spent a few minutes sharing our stories and then we answered questions from the audience. It was amazing to hear the stories of the other parents up there with me, they were all different (in terms of what biomedical treatments made the biggest changes) but ended up almost the same - with pretty much "normal" kids (whatever normal is, ha ha) leading normal lives with friends, sleep overs - in mainstreamed classrooms.... wow, it brought tears to my eyes.

Good luck to everyone out there who travels down this path, I highly recommend giving it a try. You have nothing to lose!

Lisa