Also the amount of cannabinoids DixieX is citing is actually the minimum CBD content. They show their lab results on their Facebook page. The reason the don't cite the CBD content is because CBD is illegal, but hemp products are legal if the THC content is below a certain level. They're trying to play it off as a legal grey area and are taking a calculated risk.
And I don't mean 25-50% of the plant mass, I mean CBD will often make up 25-50% of an extract. (Wikipedia has my back with a 40% figure: http://en.wikipedia.org/wiki/Cannabidiol)
Fiat non-psychoactive, not fiat legal. It's definitely still illegal. But it's included on all the lists of non-psychoactive cannabinoids.
As for that journal article, it's behind a paywall even though it's from 1940 so I can't comment on it. But if you look at the menus for any dispensary that tests for both THC and CBD, you'll see that CBD is rarely a significant percentage of the cannabinoids, e.g.
Cannabidiol is most definitely illegal in the US, too. That DixieX site you link to is just hemp oil products -- no psychoactives.