>>280058269
I'd call it just about perfect. FSN is all about the relationship between Servant and Master. Even if it's the most evident in the Fate route, UBW and HF also emphasize it. Sparks Liner High is essentially the final bit of payoff for Shirou and Seiba's bond (if you want to exclude Last Episode, which I don't).
It's all one massive callback to start of the VN: instead of Shirou holding back his vow to protect Saber from danger, he's holding back his emotions that come from him having to take her down.
It's a bit hard to articulate it, but Dark Saber (or Alter if you're inclined) being defeated by his hands is the ironic answer to the drama that existed in the Fate route regarding Shirou not wanting to let his little qt3.14 sword girl fight for him. He proved to her that he'd protect a person like her from even the strongest of foes if he put his mind and soul to it, but also inadvertently confirmed that they'd be nothing in the HGW without eachother. Shirou's spirit, aspirations, and body had already been destroyed in the time between him losing Saber and confronting her for the last time, but his mind managed to break only when he said his final goodbye to the Servant he cherished dearly.
Hell, he even proved that they were equals in strength by using a "special move" that Seiba had specifically told him not to attempt until he was as strong as his opponent. If there's one thing Nasu's really good at, it's making setup that you didn't even realize was setup 50 hours in hit you like a truck the moment it gets utilized.
>>280058551
That's a question mark, dummy
>>280058609
>I swear Fate Shirou could have caught Archer off-guard with that shit.
Archer's amazing at jobbing to Shirou's unconventional, stubborn tactics. Railgun Seiba from FHA is the greatest example of that