Parents algorithm always works, the one described has a massive failure mode - people slowly learn that they are likely to say 7 and self-censor by picking another number. Or maybe in a different culture the distribution changes (say China and the numbers 4, 8).
Except this presentation explicitly states that they don't really know what it does to proteins, only that the changes are "complex".
And you can turn your argument around. Why everytime "science" is involved, the immediate presumption is that it's safe, especially when it's done for profit and when we know you can pay to get whatever "science" you want. Remember the many studies funded by the food industry that showed that sugar is perfectly safe and that fat is the dangerous thing?