Not quite the same, but it rubbed me the wrong way…
A few weeks ago I saw a video of a red hot metal ball being dropped into a bucket of water, peculiar reaction ensued.
Someone asked what the heck just happened and posted two comments, too long for a single one, explaining about the Leidenfrost effect and some hypothesis over what was going on.
Here comes the thing, after my post other people start answering the same question pretty much verbatim to what I had just wrote; I felt like back in school with the class numskull peering over my shoulder during an exam.
I have some videos up featuring Bulgarian choral music, which I love. And I have to keep deleting idiotic comments about who killed who, and who over-ran what and why people should keep the same ancient battles going for another few hundred years.