Sure. I'm not exactly sure why you'd choose to interpret "read up on brainwashing" in this context as meaning "read what a member of the group you're concerned about being brainwashed by has to say about brainwashing," but I certainly agree that it's a legitimate example, and it has exactly the failure mode you imply.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.