Is it possible that there may be another side of Paleo which we have not really gotten the chance to dig into yet.
For example should someone originally from Eastern European descendant try to mimic what their ancestors 20,000 years ago ate. And people of African descent try to mimic what their ancestors ate, etc. 20,000 years ago we had already migrated all over the world. http://www.roperld.com/homosapienevents.htm
All these eating styles would still fit into the Paleo framework however maybe if we researched it it may help answer some questions as why low carb works for some and medium to high carb works better for others. Also maybe give us some insight as to why some fructose from fruit is ok for some but does not work as well for others.