During my military radio ops course, I realized that the woman teaching us about different frequencies literally thought that 'higher' frequencies were higher off the ground. Like you, I found her explanations deeply confusing, though I suspect most of the other candidates would have said it made sense. (Despite being false, this theory was good enough to enable radio operations - though presumably not engineering).

Thankfully I already had a decent founding in EM, otherwise I would have yet more cached garbage to clear - sometimes it's worse than finding the duplicate mp3s in my music library.