As always, my perspective from my journey down the rabbit hole gives me a different perspective on this from everyone else.
Early in my illness, I had some mild trigger point pain (e.g. feeling like stiff hamstrings). After a few years, this went away. (I wonder now if that could have been related to my starting on the anticonvulsant drug Lamictal.)
For a short while when I was doing a trial of an antiviral, the trigger point pain returned, to the point where I could barely walk. Then it went away again (as I got sicker).
After I moved out of the moldy house, went to the Godforsaken desert, and started detoxing like crazy (with the help of cholestyramine and methylation support), the trigger point pain returned. This was problematic not so much because it hurt unbearably, but because it clearly was related to my detoxing effectively.
What I now believe is that the trigger point pain is due to the fascia being all "gummed up." William Rea talks about this concept in his book. Enough toxins turn the fascia (which should be sort of a gel consistency) hard (more like a cross between styrofoam and stuck-together saran wrap), thus impeding the lymph and electrical impulses (and to a lesser extent the blood) from flowing through. One interesting thought here is that gliotoxin (a toxin made by candida and aspergillus) substitutes for glutathione in the fascia, making it all gummy. But other toxins might affect it as well.
I've managed to address this problem with neural therapy and other bodywork. Lymph massages are supposed to be helpful too. One thing that's also helped is a probiotic called ThreeLac. I hate to sound like an ad, but this seems to have a much better effect than other probiotics. Most probiotics have Lacto bacteria in them, which is inflammatory. This one appears to be anti-inflammatory. Rea suggests that inflammation can be an issue with the fascia, and controlling yeast (which could be part of the goo since it spreads throughout the body) seems only helpful as well.
The toxins flow out much more freely now that my fascia is in better shape. I'd never have gotten anywhere with them if I'd not addressed that component.
RE not having pain throughout much of my illness: I feel sure that for many years during my illness, I was releasing no toxins whatsoever due to my severe methylation block and heavy mold exposure. (The body refuses to release stored toxins when the external toxic exposure is high.....the combination of the two is too stressful and a natural defense mechanism kicks in, I think.) And if there are no toxins that are on their way out, it doesn't particularly matter if the fascia is gummed up in terms of pain. (Electrical impulses and blood circulation is impeded, but those don't create pain.)
I believe that severe headaches in CFS are associated with the stuff I'm now calling the "?" (an outdoor biotoxin that made me really sick last summer in Lake Tahoe). My belief is that if people are getting severe headaches on a daily basis, and especially if they're severely sick in other ways, they might want to consider moving out of the area. Whether the home has mold in it is irrelevant, if that's the case.
Of course, no one has to believe anything I say about any of this....
Best, Lisa