Ano zauważyłem że to polskie wideo, witam To angielskie forum więc odpowiem in english.
In the first video he makes (about lines) the bad ones are actually good, and the "green" lines are bad. Look up this video to get better understanding about how racing line is actually made and why.
It shows why it is a myth that you should concentrate on getting the best exit speed possible.
In the second vid (the one posted) the graph is really wrong, it should be a quarter-circle not a straight line from 100% braking to 100% turning. (that's why it's called grip circle, not grip square)
And really if you pay attention to the vid I mention earlier, you'll know that you want to brake and turn at the same time and how and when it differs to his ideas.
TBH i only skimmed his video, but there was a lot of poorly explained stuff, that could be passed as "ok" if understood correctly, but then it was often not clear "how" or "why" so there was just as much probability for misunderstanding if you aren't already good at the topic.
If you have some specific question about particular claim in that guy's videos we can discuss them, but otherwise im not wasting my time on correcting random videos.
Funny how you learn more from a small but polite bit of conflict, i probably would have ignored
the second posted video, certainly the first, under most other circumstances, but watched it all and learned a lot.
I just tend to write what i think, getting polite grief from that tends to make a new and more
profitable understanding. And also seems to etch it into my brain better.
So cheers for that chaps.