But most of the time people wi heal with the quartet? I assume "wi" is a typo for "will'. I would say a lot of people have a chance for substantial improvement. How far that goes depends a lot on how good they get at following the clues, how much actual damage and what kind of damages they have as compared to recovery of function. Also, there are at least 20 or 30 items that feed into it. There is a lot of co-morbidity of possibly completely different causes. There are no guarantees in any of this. I had to do a lot of physical rehabilitation to regain my muscles. Also, how do you define "heal"? I am healed from CFS/FMS and congestive heart failure but if methyltrap returns I could develop it all over again in a year of methyltrap. I no longer have the symptoms of CFS, FMS or congestive heart failure. Symptoms can start returning in 3 days if I can't get a 5 star MeCbl and a little longer if I can't get a 5 star AdoCbl. Too much of some vitamins and methyl block occurs. However, FMS/CFS/ME is more than a few deficiency symptoms. It takes a long time to develop these diseases as a whole complex of symptoms and damages. Sub Acute Combined Degeneration is in substantial remission but that only means I'm maybe 6 months from a wheelchair. I was within some weeks or so at one point. That isn't part of the definition of CFS/FMS/ME, but as far as I can tell that is a prolonged and very serious version of them. There is a continuous progression towards them as symptoms intensify and stick around. It took 3-4 years for the first symptoms of that to appear after entering methyltrap. Is there any way to determine what vitamin may be responsible for the deadlock other than trial and error? There is a mistake in assumptions right there. All four usually affect the deadlock. The relative seriousness of each determines the mix of symptoms and damage. Because of various patterns I would be inclined to say that genetic issues are probably the cause; polymorphisms affecting folate, whether a specific form of carnitine acts as a vitamin for a person, and who knows what else. These lead faster or slower to a deadlock. Trials are needed to find the best response to perhaps 20-30 nutrients in a complex relationship. I found the first 10 things or so without an error. I could have missed out on all of it by buying the wrong brand of MeCbl to begin with or chewing and swallowing it. Increasing B1 by too much can ruin everything if it is not recognized. What are you really trying to find out? People making wrong choices can be permanent or temporary depending upon the person in all sorts of ways. People choosing too much of the right thing can stop everything. It's a tricky maze. Trial and error implies some kind of randomness. That isn't what has to be done. There was a reason backed up by research of various sorts for the choice of each thing. Until one sees what remains after the deadlock quartet and obvious responses and induced deficiencies, one can't target the right things. "Trial and error" implies a completely different process than targeted choices and titration trials. The needed amount of x can change because of other changes of other nutrients. There is a strategy to it, not just throwing mud at the wall to see what sticks. Order is important. timing is important. Method is important and it isn't "trial and error".