The fact that Shannon entropy is still relevant in numerous modern mathematics research is amazing.
Apart from minor typos that make him a "sloppy mathematician", he is a good educator based on my personal experience taking grad. courses from him. He's not the passionate high school STEM teacher type, but he offers great insights. I think which textbook he used is somewhat secondary. For courses he had taught before, he usually pick a standard text and teach based on the material he wrote in his blog post, including exercises.
Apart from minor typos that make him a "sloppy mathematician", he is a good educator based on my personal experience taking grad. courses from him. He's not the passionate high school STEM teacher type, but he offers great insights. I think which textbook he used is somewhat secondary. For courses he had taught before, he usually pick a standard text and teach based on the material he wrote in his blog post, including exercises.