Quote Originally Posted by Enkidoh View Post
The second reason is more technical, I recall it mentioned (but I lack a citation on it) that due to how the Duty Support/Trust NPCs AI are scripted, they take the lead from the player's character, so adding in a second player confuses the AI as it doesn't know who to follow and potentially causes glitches and issues. Nothing particularly insolvable with time and resources, but again due to Duty Support being a 'last resort' for players to complete main scenario content and not the prefered means of completing content, this is something they're simply not going to look at I'm afraid.
This can be addressed by having NPCs take the lead from the party leader only (or "the player who is alive and ordered topmost in an invisible party list"). This would not change single player trust dungeons in any way. There would be some edge cases where it results in their behavior being unintuitive such as handing spread mechanics but the cost is worth the benefit.