Wait, isn't that the same person in both videos? In that case, this is just a marketing spot demonstrating how it "could" work, not an "A/B test".
The worker presumably has to do the same work many times. So he isn't doing the work in the video for the first time regardless. It's something he does regularly. They could do the work with glasses a couple of times and compare it with non-glass work times. I think this is (as in the video) is the best A/B test way.
I'd imagine most of the gain comes from companies with a high number of ESL workers - but it sounds like it may be a tool that a bureaucratic, control obsessed, management culture likes but is largely just busy work parading as productivity gains.
It could also make the technical manual writers lazy or use less editing because they lean on the language instead of investing real thought into making their communication effective and easy to understand.
As machine translation of english continues to improve, I'm curious how useful it will be. And the feature of "Reducing ambiguity" (according to Wikipedia) is something that can be solved in many different ways without having to invent a whole new simplified language subset for all communication.
Either way that's an interesting example of how serious they take this stuff.
I don't work in aviation, but you can produce much better documentation by following at least the spirit of this vs. the specific grammars and vocabulary.
Engineers and IT people are often not very strong in writing ability, and there are many non-native speakers in technology. I've seen situations where "Cute" documentation with TV references (infrastructure placement was captured by types of disney vs. looney tunes characters) and lots of implied context. Having a style guide that forces simplicity can be a high value.