This whole set of posts is moot unless there's agreement on exactly what "detached" or not "detached" from the market even means. Over what time frame? If a stock is up about x% from the crash of 2009 and the market is up about x%, a long term investor could say it has traded "with" the market regardless of whether its daily gyrations match the S&P, Nasdaq or some other index. A day trader or swing trader would have a different opinion.
Or you could just acknowledge that trading programs listen for keywords and trade stocks in general, based on those words.
'No Tapering'.... every single stock was bought by the programs. Nothing to do with whether something is or is not detached from the market. Computer programs listen. If Ben would have said, " oops I meant YES Tapering " a minute later, then all stocks would have sold via computer algorithms listening to him.