I run a local Tube Archivist mirror and having live, predictable full-text search of descriptions, transcripts, and user comments has been a breath of fresh air (it's backed by ElasticSearch, so you can go full-contact if needed). I appreciate YouTube's official search for its accessibility, speed, and spooky "it knew what I meant" ability, but it's a tragedy that this is the only supported way to search their library. I consider YouTube's archive a wonder of the world, and it's a shame that it is locked behind an engagement-polluted interface.