The problem with tests like those are really the uncertainties that come with the scanning process. At the start of the evaluation, the author says he reached out to the lab (that apparently did the processing + scanning) and asked if what he saw on screen was actually truthful to the negatives themselves and not the result of differences in scanning, to which the lab apparently replied that it really was the film. That, for one thing, simply cannot be true. All the images show roughly the same brightness range, which means that the under- and the overexposed shots are compensated somehow to bring them back to a convenient viewing range. If they had really been scanned identically to the normally exposed frame, the underexposed frames would be significantly darker and the overexposed frames would be significantly lighter, obviously. Hence, there are differences between the frames in the digital process. And that immediately sheds doubt on the accuracy of this test. Apart from brightness and contrast, what other tonal changes have entered the digital processing, either on purpose or by accident? We don't know, and probably never will, as likely, some of those changes will have occurred 'under the hood' of the digital equipment used.
Then there's another issue. This comparison attempts to show a sort of 'ceteris paribus' comparison: it tries to show differences in color rendering between different frames. While I don't dispute that some color shift can occur as exposure is changed (at least if it is changed significantly), the real question is: can it be compensated in printing or post processing? In other words: a color shift isn't necessarily problematic as long as you can fix it. So the real question is: is there any crossover? So far, I mostly see some shifts on Y/B and M/G between the frames and most of those would be fairly easy to remove during e.g. optical printing. Generally, such shifts are also much more dominant than crossover and need to be fixed before you can visually judge any crossover issues.
Finally, another problem pops up: if there is such a big color shift between box speed exposure and +1 stop exposure, how come the lighter values in a normally exposed frame (i.e. everything above middle gray) don't shift to significantly cooler hues while the shadows remain warm? This, again, brings questions and concerns about the methodology used in this test.
So all considered, I don't doubt the good intentions of the maker of this video, but I do doubt the methodology and in any case, by handing the most crucial part of the process to an external party apparently without sitting together with them to develop a methodologically sound approach, the results are very difficult to interpret and to me, they seem rather doubtful.
What I do take from this entire threat, however, is that I really need to get me some of this film. I have a feeling I'd like it a lot.