Supporting requirements updates during software evolution – Talk by Martin Glinz at SE 2016
Martin Glinz from the University of Zürich has given an interesting talk on a paper they presented at the RE conference. If you work in a process in which you update "old" requirements, it is difficult to identify which ones. They tried to identify the affected requirements based on a code change.
I would suspect that this is not really relevant for agile development processes. But in other context, this could really safe time.