Robb has mentioned that he'd like to work on more books involving diving deeper into the science, but that for now, he can help more people be getting people new to the 'paleo' concept to buy in, versus trying to tweak the diets of those who already eat in a paleo/primal way.

I don't believe anyone feels obliged to buy those peoples books, but that just like training someone with how to squat, by spending time with different coaches you can learn different cues. Having many different ways to explain why someone should eliminate grains, legumes, dairy, etc. is a valuable asset.

And while time is finite, I quite enjoyed spending a few hours reading Robb's book, despite the fact that it didn't blow my mind with all new theories/ideas.

Robb is THE man. There isn't a lot more left to say. As he has relayed through Professor Cordain, how can people get upset when all they're asking is for you to eat more vegetables, fruits, lean meats, seafood and some nuts and seeds?