You've given this so much thought. Your analysis intrigues me, and it makes sense to me that autoimmunity is expressed variously in different people, and sometimes within the same person. When someone suspects a source of inflammation in their life, and roots it out and calms it as thoroughly as possible, then they can hopefully spare themselves future grief and perhaps undo current grief. Hashi's as dealt with on patient groups I visit is laid to rest by suppressing TSH and letting exogenous thyroid extract provide the suppressed hormones. That helps spare the thyroid, but may not address the trigger that started the inflammatory cascade. It makes sense, then, that inflammation could erupt elsewhere, little fires that keep needing to be put out because some background problem isn't being resolved.