Plot Hole · 10:11am Jul 12th, 2022
You know, the more I think about it, the more I realize just how much of a plot hole from MLP:FiM Tirek getting letters while in Tartarus period is to begin with. Tartarus is essentially MLP:FiM's equivalent of a maximum-security prison, so that would mean letters would have to be screened period if any letters at all were to go through which would make Cozy Glow or anyone else really unable to learn from Tirek the ability to drain all the magic from equestria. But not only that, but I feel like any letters to Tirek specifically would just get thrown in the trash to begin with as he has been put there twice as it is. And for that matter, how would mail get to and from Tartarus anyways? Does like a specific royal guard deliver it or something? Even then, it would still just be the same screening process as before and then we're back where we started.
As such, this is a massive plot hole that feels like it was left completely unanswered. It's another reason why I argue that the season 8 season finale was rushed out the door because the show's writers only had one season after this to write, and it's why some of season 9 just feels like stuff that was being done as a last-minute thing for no real reason. Yet more of a reason why I believe an additional season would've fixed a LOT of issues between the season 8 finale and some of the season 9 stuff.
Good analysis.
The letter were probably just delivered by ordinary mail ponies. Considering that one of them was persistent and dedicated enough to delivery a letter directly to Discord in his chaos dimension, I can't see Tartarus putting them off, and since it's only really guarded by Cerberus, a dog, I don't think letters are really being screened there.
5671885
Discord is discord, and by season 8 Discord was more or less not as much of a concern as say Tirek who I repeat, has been put into Tartarus TWICE OVER.
5671890
It was in the smooze episode, way before season 8, and the mail pony somehow managed to get into Discord's place without Discord's help, proving that mail ponies will go literally anywhere to deliver a letter, and given that even in real life there are people who send letters to serial killers in prison, I can't see there being a particular rule against it in Equestria. Besides, given how maligned Tirek is, and how blatantly dangerous and treacherous, there's a good chance that the princesses simply couldn't imagine that anyone would be crazy enough to try and work with him again.
5671892
Okay, let's assume then that everything you've just said is a true fact. At that point, it still doesn't explain the how mail is being delivered to Tartarus if at all. In fact, until that point in the show, we are NEVER told about mail being a thing those in Tartarus even get. The fact that it's sprung out of literally nowhere for no other reason than "because plot demands it", then it begs an even bigger question of why we didn't hear about this sooner. Not only that, but wouldn't have Princess Celestia or someone else noticed that one filly; namely Cozy Glow; was doing a lot of correspondence with a known two-time felon in Tartarus? Because it'd be one thing if Tirek got letters from others, but because we don't know that, and only know Cozy Glow wrote him a lot, wouldn't that just be super shady and suspicious enough to warrant Princess Celestia being at least a little concerned? She of all ponies knows how dangerous Tirek is, so one pony being the centaur's only correspondence is rounds for at most questioning.
That's why this whole pen pal thing between Tirek and Cozy Glow feels so rushed out the door on top of Cozy Glow being a villain in the first place which I have bent over backwards enough explaining away in previous blog posts. I shouldn't have to re-explain myself for the umpteenth time how one comment about a grate is just coincidence and also bring up the ending portion of "Marks for Effort" which would go against any realistic villain behavior. I get it's a cartoon and all, but the fact that Cozy Glow is made a villain with zero actual buildup as she only appears in two episodes prior to "School Raze" is enough of a reason for me to believe that Season 8's finale was rushed out the door.