Am I to understand that you are saying that once a person has body damage caused by chemical poisoning or a destructive chemical exposure, that the person can get back to a state of total tolerance to manmade chemicals, which our bodies were not really designed to tolerate in the first place? I have never met or even heard of a person getting back to the state of tolerance they had before damage was done. Can you point me to someone who is now totally tolerant of the chemical-laden world after having been so severely damaged by synthetic chemicals? That would mean they can go to work in air freshener, perfume, cologne, ammonia cleaners, chlorine cleaners, toilet stone deodorants, use printing ink, toner, laundry detergents, regular soap and shampoo, eat in a restaurant where natural gas is used to cook the food, etc. for 8 or more hours per day, or that they can work at a chemical plant if that is where they used to work, or they can continue to live in a toxic city like New York or Los Angeles or Houston without experiencing adverse health effects from the constant exposures during everyday life there? Or can a person who used to eat whatever they wanted go back to eating like they did before they were damaged without experiencing adverse health effects?
I am not saying that someone can't get somewhat better than at the worst time of their illness, but I have never heard of someone getting totally well after having such severe damage from a chemical exposure that they black out, have seizures, have one side of their body stop working, go into anaphylactic shock or respiratory distress, etc. upon synthetic chemical exposures. The people that I know of who at first said they got "well" after developing MCS and went back into daily-life exposure to these synthetic chemicals became as sick or worse after doing so.
From what I can tell MCS is no longer controversial in the medical community, well, maybe that term "MCS" is controversial, but the term "adverse effects from chemical exposure" is not controversial and isn't that what MCS is?