Mmh, IMO you say too much of the story. Well, if I had to read Blame! again without knowing it already, I really wouldn't want to have even a tiny idea of what the megastructure is.
I once made an article, and I guess what I said is that it takes place in a degenerate, apparently endless city, that feels almost a character on its own. But not much more. I try to give an idea of the mood, of how Nihei doesn't give much informations and all, but I would really not say that it's a dyson sphere past mars, etc etc...
Except that, good article, the beginning feels a bit fan-boy-ish, but the rest of the article explains well how one can be so passionate about Blame!
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