I liked this better than last week's episode. But if Barry went back in time with Thawne to restore the timeline, I don't see how there could be a Timeline C, which was a slight variation of Timeline A (original).
As Jay said, you can try to put things back the way they were, but the fact that you intervened in the past at all means that the initial conditions will be slightly different, and that will have some impact down the road even if the broad strokes are the same. So you'll never be able to mend the "cup" perfectly without a couple of "cracks" remaining. I think Barry's drawing was misleading -- the "third" timeline he created was essentially the original one with a few subtle tweaks, so it should've been drawn right next to the original one instead of on the opposite side of the Flashpoint line.
After all, the thing to remember is that there are two other shows set on Earth-1 and they have their own writing staffs and their own stories to tell. So it was always a given that whatever changes Barry made would have minimal effect on anything beyond his own show (I'm surprised they did the Diggle-baby change at all). As far as
Arrow and
Legends are concerned -- well, at least as far as
Arrow is concerned -- the timeline needs to be the same as it was before. So it's better to think of this as a slightly revised version of the original reality than as a separate reality altogether.
I must admit, part of me longed for Timeline A by the end of the episode just because the relationship dynamics were so much better, with less drama from Cisco and Wests.
Yeah, but they mended those rifts by the end of the episode. Iris forgave Joe and kissed Barry, so she's already back to where she was at the end of last season. Cisco's still mourning his brother, so that's a change, but he's made peace with Barry and gotten back into villain-naming mode, so he's starting to get back to normal now. And he's able to harness his sonic Vibe powers, but that's just a shortcut in the arc he was already on. So very little has really changed, aside from Caitlin having powers and Draco Malfoy working in the crime lab.
I am curious how Barry's trip to the past changed conditions so that Caitlyn is now a metahuman. That one doesn't make any sense to me.
Well, Caitlin's Earth-2 counterpart had powers, so it was the luck of the draw that the dark-matter wave somehow skipped over her on Earth-1. Think of this timeline as a do-over. The same events were given a second chance to play out, and most of them happened the same way, but some things -- things that were matters of chance and could've gone either way -- just randomly fell out differently.
It's like running simulations. If you look at FiveThirtyEight or other election-forecasting sites, they talk about how they run thousands of simulations of the election given the polling and demographic and economic data they have, and they get a bunch of different results that show up on a bell curve, with some outcomes happening more often and others more rarely, but still not all happening the same way even with the same starting parameters. So in this case, if you simulated the dark-matter explosion a bunch of times, maybe Caitlin would get powers in most simulations, but would not get powers in some of the simulations. And old Earth-1 just happened to be a run where the dark-matter wave skipped over her for some reason, but now that the "simulation" has been re-run, that didn't happen this time, even though the starting conditions were basically the same.
