Not to start another war here, but I do find the hijacking of posts to be problematic, but for a very practical reason that some may not have considered. We are all familiar with the phenomenon of people starting new threads asking questions that have been addressed dozens of times already on this forum, and we have probably all wished at least once that someone had done a bit of searching the forum before starting a new thread. But as someone who has tried to do this before, when I see a topic about, say, "sharpening advice," and it has 10 pages of comments, half of which are about the virtues of, say, white #1 vs. white #2 after someone has hijacked the thread, I am not going to spend the time reading that post, because the time involved cannot be justified given how many of the comments have nothing to do with the title of the post and the subject I want to research. For the sake of archiving/searching, therefore, I do think it would be more appropriate for people who want to discuss something unrelated or only tangentially related to the topic introduced by the OP to simply start their own thread.
Just my 2 cents. And this of course does not apply to the Popcorn Protest, which I agree was brilliant.