It puzzled me too! As you know, I'm extremely -- perhaps indeed overly -- capable of finding a lot of things funny, whether or not they were intended to be so, and thence often comes my enjoyment where other enjoyments may pall. But this book is very serious about itself, and is also perfectly competent and not at all ridiculous, thus actually diminishing my personal enjoyment more than if it were somewhat less competent but more entertaining as a result.