I rather admire this as an exercise but i'm not quite sure what the point of the exercise was, as such. The book doesn't quite stick to it's conceits firmly enough to be a creation of pure style. It's gimmick is telling a handful of tightly focused murder mysteries (pleasingly clever ones, for me anyway) that are seemingly only small parts of a much larger galactic-rebellion, search for FTL, etc Space Opera type story. The mysteries are basically incidental - the effect achieved only by looking at the 'history' through a tube. This is the neatest thing about the book, and I feel a bit let down that it rather sprawls towards the end, actually telling the space opera rather than just implying it. Then again, perhaps the odd sort of ghost-vision effect, of staring at something random until it starts to get a shape, wouldn't have been so strong. So I disagree that the ending was too abrupt - to the contrary: it wasn't abrupt enough. But what we were supposed to see in this juxtaposition of the two still remains, well, a mystery.
