I tried T2 5 years ago and didn't notice anything.
A tad off topic, but the combo of T3 & Vyvanse took me from mostly bed ridden to functional. I have Hashimotos, but my T3 & T4 levels never went below the bottom of the "normal range" & I do have ME, OI, an antibody subclass deficiency, Lyme & hhv6.
Now, despite only treating my Lyme with 3 Mos of doxy & not treating my hhv6, I am able to work a normal job and handle light exertion (i.e. carrying my groceries up the stairs, cleaning the bathroom) taking only the Vyvanse & T3.
The IVIG takes my residual fatigue down a notch and prevents me from getting sick every time I go to a crowded public place, but the Vyvanse & T3 are the core reason for my functionality. Without the T3 & Vyvanse (even with IVIG), I am severely fatigued, orthostatic, gain weight very rapidly, and can't think unless I'm horizontal.
NDT didnt help me much, only Pure T3 thyroid hormone (compounded into an extended release form) because it turns out I convert my T4 into reverse T3 (inhibitor of T3 receptors) rapidly & NDT is mostly T4.
So if you don't/didn't tolerate NDT or synthroid, it may be because you make too much Reverse T3, which can be genetic, caused by high dose steroids & certain beta blockers, infections, autoimmune disease, sleep deprivation, or inflammation/stress.
Pure T3 (compounded extended release or less ideally, cytomel) would be the way to go in that case, but adrenal function must be checked and any deficiencies must be treated before/while thyroid hormone is started or an adrenal crisis can occur.
Aditionally, iodine deficiency will limit the uptake of thyroid hormones into cells (they don't just diffuse through into the cell nucleus as was taught for decades) as well as their production. Signs of iodine deficiency can thus mimic hypothyroidism, but a standout symptom is inability to sweat much/normally.
Iron deficiency (low ferritin, even if your hemoglobin is normal) can also mimic many low thyroid symptoms & be a cause of restless leg syndrome and tinnitus (ringing in the ears).
Immune deficiency & chronic infections can cause fatigue that persists despite treatment of thyroid, adrenal, iron deficiency, and iodine deficiency. So if you got sick often as a kid, have an autoimmune disease, OR if the only symptoms of a cold you seem to get are fatigue and maybe some sore glands/throat while everyone else has a raging fever, cough, etc -- get checked for an immune deficiency (CVID, subclass deficiency, NK deficiency, etc.), & chronic infections (EBV, parvovirus b19, hhv6, lyme, etc.).
Hope that helps someone or another.
