Possibly the single worst episode of The Flash. Anti-climactic and nonsensical, and with some truly terrible story decisions.
Barry simply can't do what he did at the end of the episode. It would create a paradox. Although there's good reason to think he's slipped into an alternate reality. When he travels back to Nora's death, Barry from 2015 was there, but future Barry should have been there too telling his 2015 self not to intervene. He wasn't, so this can't have been the same timeline.
Terrible decision to have Shipp play Jay Garrick. I've come to hate this fanboy thing of trying to shoehorn in connections between characters for no other reason than they're trying to be clever. I think it probably started with the Tim Burton Batman film, connecting Batman's origin with the Joker and vice versa, until today, everyone seems to be connected. I cringed last episode when they revealed Garrick was Barry's grandmother's maiden name. Enough, already. You're clever. We get it. Move on.
At least he plays the Earth-3 Flash, and there's no good reason to ever bring him back. Ever.
The Rebels' (Joe, Iris, Wells et al) plan was a bit rubbish. Send Zoom back to Earth-2 and close the breaches. But Zoom now has the power to open the breaches at will. And the breaches had been closed 'forever' once before. And were opened again.
So there's NO speedster Jay Garrick on Earth-2? Where does that leave Hourman's appearance and JSA name drop at the end of Legends of Tomorrow? They can't be from Earth-1. Why has no one mentioned them? If they're from Earth-2 they can't have had the Jay Garrick Flash as a member. And why didn't THEY try to stop Zoom? Earth-3? Then it's unlikely that Dr. Fate or the Spectre are members. Surely they wouldn't have left their Flash to rot in a prison cell, and would have been able to track him down. So are we going to get to see Earth-4? Presenting us with a Jay Garrick-less Earth-2 JSA would be truly lame.
Speaking of truly lame: Another two time remnants. Deus ex machina at it's best. Cop out at it's worst. And still impossible.
And as Reverend Meteor pointed out, even the dialogue seemed forced and unbelievably bad in places.
0/10 for this episode. Did I say 'possibly' the worst episode? Scratch that: It was THE worst.
Must try harder next season.
Thinking about it, I seriously doubt that the restored timeline will be continued far into next season, unless the writers are going to be suicidal enough to say that the first two years never happened, or we get some dumb merged timeline where Seasons 1 and 2 happened, but the Allens and original Wells exist (shudder). So what can they be planning?
Best case scenario: Barry's constant screwing around with time combined with Zoom's multiverse-destroying machine causes Earth's to merge. We'll have a few Crisis/Flashpoint style episode, then the status quo will re-establish, but merged with Supergirl's Earth, and maybe a few others. Maybe the Allens will be back. Maybe original Wells with his wife and Earth-1 Jesse too.
If that's the case, I hope the outcome is that time travel is made far more difficult for Barry - almost impossible in fact.
No more paradoxes. And no more time remnants.