Seems to me Twilight should have Discord's job and Discord should be sending Celestia letters.
Discord:"Dear Princess Celestia.
Today was my first day on the job as Twilight Sparkle and quite frankly I can see why your students either abandon you or go psycho. I have enough books here to cause an avalanche and the pony's here in Ponyville can not comprehend the concept of healthy eating as they all seem to be sugar addicts. The closest thing to healthy eating here is apples, which are abound thanks to the Apple family. I swear if I see, hear about or taste anymore apples i'm going to burn down the Sweet Apple Acre and when I do it will not be thanks to the assisted flaming efforts of the dragon assistant/mail porter Spike as he likes to be referred to (apparently he was not okay with me calling him Puff Job). As you my might of know by now I had to send this letter with my own magic instead of the simple dragon method because I had to restrain Spike do to his constant screaming things like, " Were the HELL is Twilight?" "What have you done with her?" "You won't get away with this!" "Put me down!" "Not the box! Anything but the box-!"
Anyway he'll need time to get use to the new status quo while he cools off in his small cubical room. I'm afraid i'm prattling on so anyway, back to the subject a hand. You ponies are fare more chaotic then I every hoped to be. Growing up as a young draconequus I dreamed of being the best at .....
Celestia: Oh dear me! Luna wake up! We have situation! Luna! LUNA!
Agreed, he would have been laughing his head off, so much chaos and he didn't have to do a thing! You've made Discoord proud Twilight. He probably didn't appear because he could switch things back too easily and twi would never become an alicorn.