Thinking of writing my thoughts after each episode. Might as well start with this one!
This episode is definitely one of my favorites so far this season (the premier is still at the top of my list). Although I liked it more visually than for the story. The episode is fun to watch as there's so much going on with Discord's actions, the song being the highlight, but the story didn't draw me in as much. The lesson didn't feel that legit either, it was similar to 'The Best Night Ever', except more out of place. Cadence still had a good day despite Discord trying to ruin it, but I don't think they really learned anything here. Perhaps instead Twi could have learned to tell Discord 'no' in the first place, and to not put up with his shit. Or/and Discord could learn that he can build friendships without being a dick to Twilight, though from his reaction to Cadence and Twi still bonding, it seems his motive may have been more to piss Twilight off? It's hard to tell, but that's what's great. Discord (even though not fully reformed),doesn't fall under being a good or villainous character. he could be legitimately trying to make friends, or could still be scheming something, who knows? It was nice that him and Fluttershy write letters, after the season premier it seemed that he had forgotten about her (not remembering her name).
I would also say this episode was quite slow to start, Discord's interaction with the mane 4 were fun, but afterwards we were already at the 10-minute mark. I realized this first time watching and was worried about what happened with the ending for 'Keep Calm and Flutter On' (good ending but happened too quickly). Despite that, the rest of the episode flowed pretty well, nothing felt rushed and Discords song worked well to drive the story.
Also, Twilight was adorkable again, wearing her Starswirl cosplay (the most accurate one of course!). Cadence was pretty good in this ep too, but she's still... too polite? i don't know... It just felt kind of cliche when she said she still enjoyed her day despite discord being an ass. It reminded me of 'Games Ponies Play' where the inspector suddenly picks Ponyville based on someone else's descriptions.
The Tazlewurm (however you spell it) was interesting, and made for a pretty cool fight scene Plus payed off when it came back to infect Discord. The fact that Discord was faking illness the first time makes this episode more fun, he's the perfect character to use for this sort of thing.
I enjoyed the song, though i think it's definitely one that you have to have visuals to go with it (I've yet to try listening to it without animation). The animators also outdid themselves with this, the only other thing i would say is that the music could have been a bit louder in this song. The amount of references in this episode/song where also fun. They didn't feel too forced or out of place with a character like Discord. And there were no references that were distracting if you didn't know what they were from. There was also some good throwbacks (looking for Fluttershy under a tree, Rarity's fainting couch, BBBFF Twilight squeaky toy)
Discord also wins best face:-
Looking forward to next weeks Weird Al musical episode. Two guest-star episodes in a row! 'Simple Ways' sounds fun after that too.