Also, I've mentioned this before, but I just started the second season of Unlimited Budget Works, and I still think that the show would be vastly improved if Shirou were hit by a bus, impaled, or something. Pretty sure I was told that I need to play the game to understand why he is the way he is, but gosh it just drives me crazy every time I watch. Rin for the Win. Also, I'm really hoping that this season doesn't turn into a Repeat of the "Save Rukia from the Soul Society" Bleach Arc. Get Saber back in the next few episodes because I miss her :/
There is a law: It doesn't matter how justified something is, if it just gets on the nerves of its audience.
For example Sasuke from Naruto is perfectly justified in whining all the dang time, but it tires the audience.
A lot of the time excuses are just... well... excuses for making a better character. I've seen enough cheap characters in my lifetime thanks to my obsession with interesting/great premises instead of just seeking out commonly known great animes.
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But more specifically if they couldn't fit in the scenes required to make you understand a character... they should have toned them down.
IIRC ufotable is making the anime for people who have played the VN, so lots of stuff is poorly/briefly explained. Shirou's character actually isn't terrible, it's just that he comes across as a total asswipe at first glance.
I disagree, he IS terrible, and having to listen to all his internal monologues is even worse. (Especially his two page eyefucking of every female character whenever they come on screen; which is annoying for being boring as sin to read, over and over again, more than just for being sexist.)
Shirou is, by far, the least interesting and most aggravating character in the entire series, and this makes an otherwise intriguing (though badly established and inconsistent) setting painful to experience solely because the point of view is anchored to the most boring thing in a forty mile radius.
He's bad tempered, misogynistic, stupid, impulsive, and yet refuses to kill anyone in a to-the-death melee. The very fact that he doesn't get instantly off'ed by a Servant two seconds into every engagement is both insulting to the characters he is fighting (which are supposed to be legendary heroes that can slay armies and dragons, but can't handle a teenage boy with a rolled up newspaper), and completely devalues the entire setting. Shirou is the very example of an incompetent character that only succeeds because the plot decides that he must, despite all evidence to the contrary.
He is just barely above Shinji Ikari for the title of shittiest protagonist, who himself sits comfortably above Tatsuya Our Lord And Savior.