Welp, can't think of a better place to ask this, so:
I just finished watching Clannad, after seeing various random sources saying it's the best anime ever. Personally, I don't see what everyone was going on about; to me it just looks like K-ON* with overblown amounts of emo and deliberately shameless attempts to make people cry. Which, by the time the really bad shit started happening, had well and truly lost their effect. I kid you not, I never saw the second one coming until about 2 minutes before it happened, and my first reaction was: "This caliber of tear-jerking didn't work 20 episodes ago. Stop trying to milk it already".
Anyway, back to the actual question here:
Can someone explain what the hell the last few episodes were about? First they're dead, then they aren't and it was... what, all a dream? An alternate world? A preclusion? How does that "other world" explain the apparent ability to re-write 5 years of history in what, as far as I can see, is supposed to be a relatively realistic anime setting? Most of the animes that have time travel or alternate realities in them are deliberately futuristic / fantastical, which this one doesn't fit into at all.
Were the writers just pulling a Dallas on us, or does this crap actually fit together somehow? I can't shake the feeling that, in the original visual novel Clannad was based on, the After Story part could go either way with regards to their fates, and the anime writers couldn't decide which one to use in the series, so they invented a completely nebulous plot device (read: the other world) to use as a way of having both endings in the series. Of course, if anyone knows or has seen said visual novel all the way through, please feel free to clarify this, as I'm having no luck at all tracking down the details of that particular part of it.
*I am well aware that K-ON came out after Clannad. I watched the former first, so in my case Clannad reminded me of K-ON, not the other way around.