If you look at the video, they appear to be running crown impact tests. Except one of the helmets slips and hits at a different angle. (And I'm not talking about where they have deliberately tilted the helmet on its side.)
And then they publicize it in a video? Incompetence in action.
Also, at the beginning of the video, they seem to depict the free drop of a helmet, which then wobbles about because they don't have a proper test rig. in addition, I don't know anyone with their neck at the *front* of their jaw - yet your Brit examiners have a test rig that places the "neck" pivot near the chin bar. This can and will distort the data.
Next, Snell doesn't "big" itself up. The market itself has pushed Snell forward to its current prominence; it wasn't self-promotion. It's much like Underwriters' Laboratories and household electrical gear; nobody in their right mind buys a product in those arenas that doesn't have the endorsement/certification on it.
While not as incompetent as I'd initially feared, coming from the Brit government, it certainly isn't even up to the arguably laughable standards of the US DOT test, let alone Snell M2000. At least the US DOT test has the virtue of being rather more realistic with the head form and it's repeatable with most variables removed. What I'm seeing in the video is, well, pretty amateurish.
FYI, I have dealings with businesses in the UK on a regular basis and my cousin is a successful UK video game designer who recently emigrated to the US and still has to deal with the UK government. I have more than a little taste of the incompetence of the UK government over the past 15 years.
That said, this is not a bad idea. However, they seem to have gone about it TopGear Style - "ambitious but rubbish."