I partially agree. However, the key word in your comment is "simple". While, obviously, it is subjective, in my opinion, presented diagrams are hardly very simp

I partially agree. However, the key word in your comment is "simple". While, obviously, it is subjective, in my opinion, presented diagrams are hardly very simple (though, they are not that complex either). Yes, they are readable, but only after spending some mental effort that could be directed to better causes. Perhaps, a use of Unicode-defined pseudographics would improve the readability.