Stories; Past and the Present

This is about the Time spell. Twilight is from the Future from the Perspective of Guardians of the night. And Twilight really doesn't know if Starswirl has Lived at that time or not. and as such she says nothing about "Fixing" the Time spell.

Starswirl was the one that Invented the spell in the show, and if she claimed to "Fix" the spell that would technically mean that she would have been the first one alive that knew of said spell, and therefore taking the credit for the spell away from Starswirl. If he was alive though. Then only the Princesses and himself would know about the spell because it could destroy everything if put into the wrong hooves. Even in its original duration of a few seconds.

(The Potion in Twilight's Kingdom doesn't count here.)

That is my logic for why it Didn't last for a few seconds, and why she didn't state that the Time Spell was fixed.