The point of "Embellishment for the sake of the story" was also raised in the pre-reader IRC. Thinking on it, it's a valid interpretation. I'm still bothered because I've come to see Celestia and Luna both as nigh-omnipotent Goddesses, and... I don't know, maybe it's that view, plus time constraints on the show, that bothers me. Several of the other pre-readers are also of the opinion that it could possibly have warranted a movie unto itself.
I'm feeling better and less... depressed, perhaps? over the episode. It still bothers me, but I can see where some of the issues lie, and why, now.
Sorry to be such a downer, everypony.
Also, Phoe, one of the three blogponies, went nuclear with happy when Lyra spoke :3