I posted my comment to the review itself. Basically, I think it makes good points, but as a review I think it misses some of the things a review needs. I don't object to what's said - I have a player with opinions almost identical to der Kluge's and der Kluge does an excellent job of characterizing the way that rules-heavy players will dislike C&C.
I think reviews that clearly state when the reviewer dislikes (or likes) a game are good reviews - that's not bias. I think der Kluge could have expressed his dislike far more fervently than he did and still not have a "biased" review - but not to mention the positive points leads to an incomplete review - and an incomplete review that focuses on the negative is a biased review. So, I think the review does end up being biased - not because of what der Kluge said, but because of what he didn't bring up.
For example, I think a C&C review is incomplete if it doesn't mention lower prep time or at least mention that the game's simplicity can be viewed as a positive by some people. Lower prep time probably isn't a big deal to der Kluge as a player, but it's an almost universal comment from people who GM the game. I think a review has to mention both sides, even if the conclusion is absolutely to one side or the other. Otherwise it fails as a review.
For what it is, though, it's good. Like Scadgrad says, it reflects considerable effort and thought. I think it's an excellent summary of one side of the C&C debate. Not a good review because I think it misses some vital elements of a "review," but an excellent essay.
EDIT: on the point about how it bridges editions, it would be a violation of the OGL for TLG to make a statement about compatibility with the D&D trademark.