I liked the text about typeclasses. It is a standalone piece, "Typeclasses 102" in LYaH is a part of a chapter of a bigger piece. I think you achieved your goal

I liked the text about typeclasses. It is a standalone piece, "Typeclasses 102" in LYaH is a part of a chapter of a bigger piece. I think you achieved your goal - your Pokemon example is simple to grasp and shows how to derive type classes and implement functions by hand:) (not commenting about monoid/subgroup part)