Dr. Gary Keil

Thank you so much Gary for this lovely reply. As you say, central sensitization is just the beginning. I feel like I’m getting to the limits of my understanding when I try to explain beyond this, for example I considered including the work of Apkarian which I have been reading recently, or how “predictive processing” might fit as a model of pain (having followed Mick Thacker’s work) but I am not nearly sure enough on my feet with this stuff yet. Maybe later I can write another article on more “cutting edge” models for pain. 
I hope readers will follow your advice for further reading. I felt guilty about leaving out Bonica but I had to cut a lot to turn the history into a (relatively) short, linear story.
Thank you again for the wonderful comment,