They optimized TW with the S6, N5 and Edges phones. So much so that it gets better or equal battery life as the Nexus 6P and Moto X 2015 running stock Android with larger batteries. So I think TW is optimized in that respect.
Bloat ware is present on all Android carrier phones. But then even with the extra bloat TW gets better battery life...go figure.
How does a phone with all the bloat you mentioned and a smaller battery get better battery life than stock Android phones with larger batteries? I think Samsung is getting shorted here on TW. Does it need improvement? Sure it does. But i don't think it is as bad as some would let on.
There should be even more muscle under the hood this year if the rumors are true and a more evolved and optimized TW should make the S7 a beast of a phone.
I think Samsung's better battery life than other androids has to do with their more efficient processor and display. Those two uses the most battery. I don't think their battery life has anything to do with TW good optimization.
If Sony had Samsung hardware, their phones would last a week lol.
The 810 is a pig on power, and the screen used in the 6p has shown to use 5-6% more battery than the one on the note 5.
Don't get me wrong, Samsung still deserves credit for battery life because of their efficient screens and processors. Not because of an efficient TW.