I think the "high school math" slogan is untrue and ultimately scares people away from TLA+, by making it sound like it's their fault for not understanding a tough tool. I don't think you could show an AP calculus student the equation `<>[](ENABLED <<A>>_v) => []<><<A>>_v` and have them immediately go "ah yes, I understand how that's only weak fairness"

Oh, hey -- you're that guy. I learned a lot of what I know about TLA from your writings ^_^

Consider my behavior changed. I thought the "high school math" was an encouraging way to sell it (i.e. "if you can get past the syntax and new way of thinking, the 'math' is ultimately straight forward"), but I can see your point, and how the perception would be poor when they hit that initial wall.