The preface to this book asked forebearance from the scientist that they have "largely skirted the jargon and qualifying phrases emblematic of scientific writing". That phrase alone should have been an omen of what was to come. I am afraid if this book was "keeping it simple", it failed miserably for me. At the end of it, I was simply not convinced I knew what the authors meant by "facilitated variation" - which was basically their aim in writing the book. I think that they were trying to say that there were some "core (cell) processes" coded in our DNA that evolved about a 3 billion years ago that enabled evolution. And that these processes haven't changed much. But by the weak anthropic principle, if they had changed and it mattered, would we be here now discussing it now? I therefore probably got it all wrong. The authors seem to have taken the view that if they said the same thing many times, the reader would eventually understand it no matter how it was explained.
I am happy to take the blame for not understanding the convoluted and repetitive language (and worse still, English). This is the second book I have bought on evolutionary biology and both seem to suffer the same contorted writing style. I am not a molecular biologist, but I am a PhD engineer with an almost obsessional interest in science. But perception is reality, and I don't think I am unrepresentative of others who would find the subject of this book interesting. Furthermore, had I written this book, I would want to know if it achieved its aim.
On the positive side, I did pick up some extremely interesting facts about evolution (especially cell evolution) that I didn't know before, and I thank the authors for taking the occassional detour with albeit with the intention of explaining their proposition.