There are two main ways to enjoy a twisty, plot- and mythology-heavy series like Once Upon a Time. The first is to endlessly analyze it, carefully examining and picking apart the smallest details to see how well the show hangs together as a whole. The second is to ignore the minutia -- or try to, anyway -- and simply take the show at face value, accepting that everything in it is, to some extent, made up as its writers go along (and that this fact isn't necessarily a bad thing).
If you tend to fall into the first camp, I'm going to recommend that you try to become a member of Camp #2 for the duration of tonight's Once. Because, in short, nothing we learn in tonight's fairyback makes any damn sense when held up to everything that's been established about Cora's early life up until this point. In "The Miller's Daughter," we learned that Cora is a simple peasant who spends her days helping out at her father's mill, lives in a kingdom ruled by Prince Xavier (and his son, Prince Henry), and promises to give Rumpelstiltskin her firstborn child. (He specifically asks for her firstborn -- you know, because he can see the future and everything.)
"Bleeding Through" basically throws all that out the window. In this newly revised version of Cora's story, she's supplementing her mill work as a tavern waitress (one who's apparently got "shifts," which means I guess that Fairy Land is unionized?), and she evidently lives in a kingdom ruled by Prince Leopold's father. (Which, granted, is what the show told us in "The Stable Boy," before changing its mind in season 2.) And though Cora delivered flour straight to the royal family in "Miller's Daughter," here she doesn't even know her kingdom's elite well enough to call shenanigans when a pretender lies and tells her he's the nonexistent Prince Jonathan. More importantly, when Regina and her mother met Leopold -- who had by then become the king -- in season 1's "The Stable Boy," there was no indication from either Cora or the king that the two of them had any previous acquaintance... let alone that they'd once been engaged for a hot second. You'd think that's something people would remember.
I know that we can try to make sense of these discrepancies -- maybe Cora moved! Maybe she cast a memory charm on Leopold! Maybe Rump's visions were misleading, and that's why he thought Regina was Cora's firstborn! -- but ultimately, even the staunchest Once defender has to know that the only real explanation is that the show's creators wanted to have Zelena be Regina's half-sister. And in order for that backstory to make sense, they necessarily had to change some stuff around. Ultimately, these inconsistencies aren't terribly important -- and they're justified by the way they weave Snow and Regina's tangled webs even closer together. That said, they are frustrating if you demand a show with a narrative that hangs together like a beautifully made suit. (Remember, though: Once is a direct descendent of Lost. We shoulda known stuff like this was coming.)
NEXT: Without further ado, your (actual) recap