The stories converge

Cosmonaut Keep's two story-lines converge over the course of the last two thirds of the book, concluding with the last chapter of the book remaining in Matt Cairns first person perspective instead of switching to the third person perspective that the far future chapters have always been written in up to that point. The path that the convergence takes is interesting because it covers why the crew of the Bright Star showed up at Mingulay and explains much more about the culture of the saurs. I think that the deeper insight into saur and kraken cultures that the book provides as it gets closer to the end is important for understanding how everything fits together but is also partly to maintain the balance between the near and far future aspects. The book definitely has a much faster pace for the last two thirds but at the same time seems to scramble for things to keep it going. If the author (Ken Macleod) wanted to provide fewer details the book could have easily been 100 or so pages shorter. Another aspect that fewer details would have provided is that the mystery and imagination that is persistent for the first eight chapters would have remained. To put it simply, there is less material that encourages enthusiastic discussion in the last two thirds of the book.