Because narrative designers were still writing the script of the campaign mode, entire scenes and missions were discarded due to story changes. (en.wikipedia.org)
Game projects will often use writers and narrative designers towards the end of a project but the role can do so much more. (mcvuk.com)
Speaking with Paul Crocker, Lead Narrative Designer on Arkham City, at rAge, he stated that «You're trying to find out the mysteries behind Arkham City, behind what is going on, all while Batman is being put through an emotional rollercoaster.» (egmr.net)