I tested the battery life of both standard config 13" with Touch Bar 2016 (9 cycles) vs 2017 (0 cycles) by looping Harry Potter at 50% screen and keyboard brightness.
Surprisingly, the 2017 version lasted for another 79 minutes, that's more than an hour! What I find most strange is that Apple didn't even change the battery size. I'm going to reproduce now, buts that going to take me another 10+ hours.