Posting here and having a youtube video disappear is not the reason the vids disappear, the events just happen close together in time. The same searches anyone here does to find youtube videos are also run internally at Youtube by mindless bots computer code combing the internets and albeit sometimes a little slower, most videos will be removed by the mindless bots that search the website to remove such content. Some will get lost in the shuffle, but that's how it works, Could be something simple like a song in the background, violence that might be a crime, maybe minors. I know how the system is run internally though and they aren't looking at message boards to find videos, it's all internal searches within youtube.com.