It does work. In the past when I mentioned it, someone provided an apparent counterexample, a search with a term in quotes that wasn't found on the page. When I reported it to the search team, they found that the quoted term was actually in a hidden submenu on the site. So the term was still on the page, but not findable with ctrl-f, except in the source.
Try it out and if you find a counterexample, let us all know.