A couple interesting papers from the Holtorf medical group recently came to my attention. These help explain why TSH-only diagnosis often does not work, and why other health conditions that are present with thyroid disorder, have a large effect on tissue hypothyroidism. Of course you already know those things, but the long lists of references provide authority!
"Peripheral Thyroid Hormone Conversion" (2014)
This paper ranges over a large number of topics, including: explanation of the deiodinase enzymes (D1,D2,D3); why biochemistry of the pituitary is different than rest of the body, so that TSH does not predict tissue hypothyroidism; how glucocorticoids stimulate D3, resulting in more rT3; the effectiveness of T3 in treating depression; supraphysiologic T3 doses effective in treating unipolar & bipolar depression; T4->T3 conversion decreased by many non-thyroid health conditions such as obesity; empirical evidence showing iron deficiency,inflammation,toxins reduce T4->T3 conversion.
""Thyroid Hormone Transport" (2016)
This paper ranges over some of the same issues as in the previous paper, and some others not previously covered, including: explains how thyroid transport is energy-based (not diffusive) outside the pituitary; how pituitary transport is different; how important FT3/rT3 ratio is in diagnosing tissue hypothyroidism; how it is impossible to achieve normal T3 levels with T4-only therapy (except in pituitary); that a very low TSH is not an indicator of hyperthyroidism 84% of the time; why TSH level is not a good way to determine thyroid hormone dose.
These papers contain fodder that can be used against ignorant GPs and endos. However, keep in mind that it is not a good idea to present this information to a doctor in the early stages of your relationship. I would not highlight the relevant issues presented, for presentation to your doctor, unless you have become disgusted with his/her lack of expertise and are prepared to jettison him/her, if the doc is one of those who cannot tolerate challenge to their authority.