Hi mdp2021 I understand your skepticism. The point is that the reader needs a fixed point to absorb the text. That's why this definition is placed. As shared in other comments, I unfortunately had to make very bad experiences. And the responsibility I perceive among others Marco (feedback website), I do not want to jeopardize. But I understand your objections.

Best regards from the Alps Renato

How do you decide which letters to highlight? Is it the first half in every case? Did you conduct any trials to see whether this yields the fastest reading speeds?