I saw angry comments regarding MC giving or teaching Wednesday Occlumency.
1) Even with Occlumency training MC can still easily bypass her shields if he wants too. That's how powerful he is.
2)Two I gave Wednesday Occlumency because there are characters that will be powerful telepaths and other mind controlling individual (Examples Roland Flagg, or Rose the Hat.)
3)There are ven demonic entities like Pennywise.