Well, I don't know if this will help you or not, but Fletcher had almost none of the "classic" symptoms, except a thin coat (but not rough). In fact, his thyroid was tested when he was younger because of that, and it was normal at that time. A couple of years ago, He developed a chronic limp, and seemed more hyperactive (that's very subjective, but I know my dog). The bad thing was ruled out, along with Valley Fever and some other things, so my (greyhound savvy) vet tested his thyroid, and it was low. We started supplementing and it did help the limp and calm him down (a bit). He also has arthritis, so he can still limp occasionally.
So, I don't think many people would think of a limp as a thyroid symptom, but there you are. I guess I agree with those who say the symptoms can literally affect any part of their body.
A second opinion never hurts.