Guess I can understand the confusion some are dealing with as Barry going back does seem... off.
As is, the first run through that time line had Barry seeing himself. He wasn't sure why and nothing seemed to immediately come of it, but then tsunami...
So, where's the other Barry? Few possibilities come to mind. First is that "other" slipped into whatever time stream that was created and is now in the future that was hopefully saved. As a totally independent time line at that point, it'll probably never be revisited unless Cisco's "dreams" are elaborated upon more. The second possibility is that Barry didn't actually time travel, but instead transferred memories/knowledge unknowingly to his past self where. Again, divergent time line no longer a factor to current plot. The third possibility is that the two outright merged, resulting in an alternate reality where the Flash no longer exists and Cisco had been killed. Given Wells' determination to get back home, this time line could be best primed for interference with the current reality we've been seeing portrayed since. Something like this is something I'd expect for next season under the premise Wells gets taken care of by the time this one ends. Fourth possibility? This is all a dream that dog from Lost is having.
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