I've come up with a 2nd possible theory as to why Fluttershy is so shy and has these random outbursts of anger and rage. Though bear with me, this may get convoluted and would most likely have to be simplified for the show.
What if the reason Fluttershy's backstory & parents are rarely explained is because Fluttershy actually doesn't remember her true past. What if her father was a hardcore war leader and Flutershy, or her actual name, Slash Wing was forced to volunteer. Thus strenghening her to be a brave, tough, and badass war pegasus. But after some sort of slip up, her father decided to disown her.
So he had a spell casted that had Slash Wing's memory resetted almost completely, gave her a new identity and personality, and banished her from Cloudsdale to Ponyvile. All the memories of the life Fluttershy thought she had on cloudsdale were actually faked from the spell. The reason she's so shy and cowardly is because that was the new personality programed by the spell. And the reason she has these freakish displays for rage and/or courage is because her past training still remains in her psyche. To this day, Fluttershy remains unaware of her true past.
Now I understand there may be some plot holes in this headcannon. Like how did she come to know Rainbow then, or how did she ACTUALLY get her cutie mark. But this is just a rough idea for now, If I come up with a way to fill in these holes, I'll update the post. But what do you think so far?
What if the reason Fluttershy's backstory & parents are rarely explained is because Fluttershy actually doesn't remember her true past. What if her father was a hardcore war leader and Flutershy, or her actual name, Slash Wing was forced to volunteer. Thus strenghening her to be a brave, tough, and badass war pegasus. But after some sort of slip up, her father decided to disown her.
So he had a spell casted that had Slash Wing's memory resetted almost completely, gave her a new identity and personality, and banished her from Cloudsdale to Ponyvile. All the memories of the life Fluttershy thought she had on cloudsdale were actually faked from the spell. The reason she's so shy and cowardly is because that was the new personality programed by the spell. And the reason she has these freakish displays for rage and/or courage is because her past training still remains in her psyche. To this day, Fluttershy remains unaware of her true past.
Now I understand there may be some plot holes in this headcannon. Like how did she come to know Rainbow then, or how did she ACTUALLY get her cutie mark. But this is just a rough idea for now, If I come up with a way to fill in these holes, I'll update the post. But what do you think so far?