This part is just for the general rambling and opinions, so if you don't care for a retelling of the episode, this is for you.
Okay. I mentioned there are some glaring, world wrecking problems in this episode, so let's start with those. Ahuizotl's plan of unleashing 800 years of sweltering, unrelenting heat clearly were about having some sort of control over the sun and having it burn this one place for eight centuries. Well, the problem here is that we have a princess who is in control of the sun and very likely would have a say in this matter. Even if Ahuizotl managed to take control of the sun or freeze it in place I very much doubt it would have stayed there for eight centuries or that Ahuizotl would have been free to do whatever he was planning to do for a good long while.
Which leads me to my second point, Ahuizotl, Daring Do and the books being real. How is it that Ahuizotl, who clearly wants destruction and misery, at least in this case, is out there doing these things with seemingly only Daring Do fighting him? If he is such a menace then I would imagine there would be ponies who know he is real and he wouldn't be just a villain of some stories. Same with Daring Do, there would have to be stories circulating about her exploits. And then there are the books. Unless Ahuizotl and other assorted enemies of Daring aren't illiterate they should know that somepony is writing about them, somepony who knows way too much to be some random pony. They could add two and two together and it would add up to Daring Yearling. Now, Twilight knew where she was born and all kinds of things from her past, and even managed to find out where she lives. Assuming all the information about her past wasn't faked (which it could have been but the location of the house being real mixes it up a bit) the bad guys could go and threaten Daring's friends and/or family, or even just hunt her down and eliminate her when she's sleeping.
To me it seems implausible that these things haven't happened yet. Yes, Daring's house was trashed which tells me the bad guys did know where she lives. …how is Daring Do still alive? I could come up with a dozen ways to kill a pony in her sleep or trap her house when she's out. Ahuizotl doesn't seem to be against killing her, after all… And again, how are there not more ponies fighting against Ahuizotl? These things really don't add up, and the plan of having sun scorch things up does not work in a world where the sun is controlled by somepony.
But those weren't the only problems the episode had. The rest of the Mane 6 agreeing to go with Dashie's plan really baffles me, especially since it hasn't been shown they are really fans of the books themselves. Rarity especially makes me wonder, since I would have thought she'd side with Twilight, as would Fluttershy. The next such scene is when they simply sit outside and watch how Daring Do is getting beaten up without even considering helping her. Maybe they were shocked that Daring Do was indeed real, but I doubt Dash would really just have sat there and done nothing when her hero was being attacked. Same with Twilight. It ended up being Fluttershy who told them they should go help her.
Speaking of Fluttershy… Thank you, based Polsky. Fluttershy wasn't a shivering, panicking mess who was afraid of everything. She was a reasonable mare who could throw a little quip or remind the others that hey, we probably shouldn't just sit here and watch. I mentioned above that her "I can vouch for that" reminded me of her "I'm a year older than you" line from GtBO, which is also one of my favourite Fluttershy lines. This Fluttershy, in this episode? I love her. Again, thank you, Polsky.
Pinkie was really good, too, I found. At least when compared to some of the horrible treatment she's had earlier. Random? Yes, of course, but not too too much. Twilight was Twilight, her talking about the perils of hero worship to Dash was a bit weird, maybe, considering how much she looks up to Celestia. However, she is the one pony with the most experience with the problems that could cause, and I personally found she could speak from experience. Maybe somepony pointing out her own problems with it could have been nice, but I don't think it was really a problem.
Rarity and Applejack weren't really focused on that much in this episode, but I did like them. Rarity mentioning she hadn't heard of this "holiday" either and just moving on to mention how good the punch was was quite delightful. It was also a nice reminder that they have been friends with Pinkie for a while now and do expect these kinds of things from her without making a big deal out of it. It's a little thing, but little things and these details are some of the things I like the most.
Then there's Dash herself. I'm not the biggest Dash expert or fan as some of you probably know. Her motivations at the start of the episode for tracking down A. K. Yearling really were rather questionable, but she ended up being just fine. I liked her slapping herself in the forest and fangasming over Daring Do, even if it started to get a bit old and she was being stupid at some points with that. She honestly just wanted to help Daring after finding out the truth but with how in awe she was she just got too distracted. This Dash? This Dash I can like, and understand.
Now, for the rest of the ponies somehow being convinced that harassing the author is a good plan… It is odd, it really is. However, and this is headcanon stolen from some fics, Rainbow Dash is the Bearer of the Element of Loyalty. It's her stated virtue. She has shown she can inspire other ponies to do things with and for her (Hurricane Fluttershy really comes to mind) with just the strength of her personality. She inspires loyalty in other ponies, and I believe this is what made the others go with her plan. Now, obviously it's not canonized in any way, so I can't dismiss that flaw in the episode, but it makes it feel better for me.
So, with all that said I did enjoy the episode overall. It had some smaller, and some bigger issues, but if you just sit back and enjoy the show it is an enjoyable and nice episode. Admittedly I'm quite the Flutterfag so her being so lovable made this episode feel better for me, as did the little friendship things in the episode overall. It is unforgivable that the writers or nobody else caught that problem with the sun and Celestia but the episodes not quite working or having some issues seems to be more the rule than the exception these days. And Polsky shows that he indeed still knows the characters for the most part. Ranking this higher than Castlemane-ia, and for the sake of this ranking I'm ignoring the premiere two parter. We'll see how Scoots does next week.