Ryan, this is great, I came here for an argument! Thanks. ("I wish to believe 'snow is blue' if and only if snow is blue")

(a) OK, can we agree on "In most cases with 'normal' 0.3<TSH<5.5, TSH is the sole test performed"?

(b1) I don't know, but given that FMS includes 'brain fog' and 'tiredness' I'd be surprised if many people with it haven't had a TSH test. I would be surprised by the existence of people who only have the tender points and no other hypometabolic symptoms. Do we know what proportion that is?

(b2) "Also there are studies where they stimulate release of thyroid humans. There are literally hundreds of highly relevant studies here." I don't quite understand what you're saying here. Can you link to a couple? Google scholar "fibromyalgia and thyroid" gives top hit: http://europepmc.org/abstract/med/1512769, Neeck G , Riedel W "Thyroid function in patients with fibromyalgia syndrome.", in which they find abnormalities in a thyroid hormone releasing test in fibromyalgia patients. Doesn't that support me?

(c) There are forms of hypothyroidism that don't show up on the TSH test certainly, 'central hypothyroidism' and 'peripheral resistance to thyroid hormone', which have the same presentation but normal TSH. 'Central' should give you normal TSH but low T4 and T3. 'Peripheral' should be normal in all respects. But they're thought to be vanishingly rare, and as far as I know, CFS/FMS people aren't tested for them. In fact presumably the only way to test for them would be a trial of thyroid hormones! That's kind of my point.

(d) Not just tiredness and slowness. It's more of a general metabolic collapse. And which systems fail first seems to be random, which is why it's so difficult to diagnose clinically.

(e) I'd expect anyone with widespread pain to recoil if you tried to touch them.

"What is needed here are similarities that are specific to these conditions and that are shared, whereas here it is the aspects that are the most general that are shared but the main facets of each condition are quite different and overall the two conditions don't blur together in an interesting way."

John Lowe appears to have known the rheumatology and endocrinology literature backwards, and claimed that every symptom of fibromyalgia was a symptom of hypothyroidism and vice versa.

He gives references for a vast number of them in:

Inadequate Thyroid Hormone Regulation as the Main Mechanism of Fibromyalgia: A Review of the Evidence

You can find it here: http://tpauk.com/main/dr-john-lowe-overview-of-important-articles/

There were a couple of hypo symptoms (low basal temperature and low basal metabolic rate), which are arguably the characteristic symptoms of the disease, that hadn't been documented in fibromyalgia. So he got a bunch of FMS patients and checked. And found them.

I really think that at this point, someone should be running a PCRT on 'giving desiccated thyroid to FMS patients'! I would actually be surprised if T4 alone didn't have some effect, but since Lowe thought (from extensive experience, but based on a sample that must have been skewed by people going to him after doctors failed to help) it was the least useful of all the thryoid hormone therapies, we should take him at his word and try desiccated thyroid. My own bet would be that T4/T3 in the same combination as secreted by the thyroid gland would be the best thing, but that's just a detail.

Again, many thanks! I don't want to have these beliefs if they're false. Take me down.