Pixie, to even add more to what you've posted, I'm in the Dr. Teitelbaum camp where he believes that hypothalamus suppression causes Fibromyalgia. In other words, thyroid, cortisol, the hypothalamic sleep center and sex hormones can ALL be affected.
Based on my own hormone profiles, they conform to Dr. Teitelbaum's way of thinking. It's important to find someone who knows what they're doing with hormone balance, who doesn't look at lab values. Because of hypothalamus suppression, lab values become somewhat useless. As a result, I've resorted to telephone consultations with a doctor who knows about hormone balance and Fibro.
But thyroid is a huge part of it. Before things got worse for me from supplementing thyroid hormones without cortisol, I had a brief period where my muscles felt totally normal. Even my RMT couldn't find any tender spots.