I like that; I think it does the job without having to throw in a lot of Scientific justification. The only issue would be having to explain why sourcing pre-agricultural foods are better than post-agricultural foods, which would inevitably lead back into the Science.

I sometimes feel that the desire to make best use of the science distracts people from the unifying principle of paleo (or whatever you choose to call it). People have science supporting pretty much any diet. We can argue that it was misused in the 1970's but all the nutritionism is still really really new and it's inevitable that we are still getting things wrong. There's still so many contradictions even within paleo and it's very difficult to nail down exactly what we mean by health before we even consider what to eat to achieve it. We have a lot of details available to counter specific arguments but Paleo isn't the sum of all these parts. For me it's the overarching hypothesis much as you describe it. The distinction is important because it informs our decisions when we aren't sure what to do.

It doesn't have to go back 10,000 years either, a lot of the principles we supposedly all adhere to were conventional wisdom within living memory. I find it's often helpful to illustrate how radically and completely we've embraced new food paradigms without question. Breakfast is the classic example, and the one which is most clearly falling down. Future historians will look on the tiny period of 50 years where humanity thought cereals were the natural, necessary and complete breakfast food as an aberration. Phrasing paleo as an anti-industry/mass-marketing driven lifestyle rather than bringing up evolution may be more productive.