I can appreciate that, but as The Hound pointed out on screen a few seasons back, all those little taps from her needle were never gonna kill Brienne. The scene was more to establish that she had potential.We know it wasn't a fight to the death. It's just more unearned level-jumping from Arya, which has been a bit of a problem for some of us over the last 6-7 episodes. She's gone from disobedient fuckup to master-level assassin/warrior in a very short period of time with next to none of her progress actually playing out on screen.
Also, in her defense we have seen Arya train on screen more than any character. Probably twice as much as any character. I think it's fair to assume she trained a lot off screen.
It's dorky, but on the list of logic-leaps the show has asked of me, that one was smaller. If anything, it felt like a course correction from how poorly she has been shown in the past. Like, it's not that this felt wrong to me, but rather that her time with the faceless men was poorly presented.