That your ability to describe something does not necessarily equate to your ability to explain something.

There are lots of examples of things that we can describe to a very high degree (life itself, for instance!) but that we do not necessarily have the ability to explain.

Ah okay that makes sense. Yeah ultimately I think Nick just gives hypothesis given what he's seen, and I'm not an expert in this field but it does seem to be driven by experimental results rather than mere description.

Personally from reading the article, I felt like it scratched the 'why' itch more than the 'what' itch which presumably is what you mean by explanation vs description but it is fairly dense and I can see how either interpretation would work.