Yes, I think concurrency is about 1/3 of the book, but it's approached the same way as the other paradigms; you have a basic language, add a single feature and

Yes, I think concurrency is about 1/3 of the book, but it's approached the same way as the other paradigms; you have a basic language, add a single feature and see what happens: what new things can you do? How does the expressivity change? What problems arise? Is this equivalent to another paradigm? I found the insights interesting, but I would agree they are not of immediate utility to many people's day job.