I didn't know anything about the topic before I clicked the link. Nothing in the comment that introduced the link revealed anything about the topic. And I only clicked the link because I was intrigued by the discussion here about rudeness. I was not motivated to click by the suggestion that watching would be worth my time (without any further details). That I found the topic interesting-sounding came after I swallowed the bait and clicked. Such things happen sometimes. And I still don't know if it actually is interesting, I won't actually know until I have set aside 3 hours to watch the video.