Oh my. Literally the things I learned/taught in my Information Visualization class. I brought this up in your intro post!

The biggest rule of thumb my professor taught us was Never Use Pie-charts unless there aren't a lot of sections and the differences among each is easily noticeable without having to rely on numbers in those sections. One of the most "eye opening" one for me was how people sometime change the scales on the y-axis to make the difference look enormous. So many tricks...

Anyways, thanks for sharing!