I noticed that when searching for a query that has no results and appending a ? at the end to trigger Quick Answer, it generates text, even if there is no search results to synthesize an answer from. I searched for "IBM InfoSphere Sensemaking" +DOD? and got a Quick Answer back:

Note that you can only force this behavior by manually putting a ? (or selecting the suggested "Quick Answer" auto-completion while typing) at the end of the query, as the "Quick Answer" button itself is deactivated when no search result is found.
I expected that the Quick Answer function to not work and not generate a text when there are no results to begin with.