What happens when the thyroid fails? How does the body react to less thyroid hormone in the circulation? Below is an illustration of a plot of the thyroid as the basis for an explanation of what is released from the thyroid.
These results suggest the existence of a functional TSH-T3 shunt that is mainly mediated via the thyroid. (https://sourceforge.net/p/simthyr/discussion/research/thread/ad36b99a/)
DT: Damping constant (EC50) of TSH at the Thyroid.
GT3: The secretory capacity of the thyroid