When making a cinematic, the map author needs to make sure the player is w/in hearing distance of the cinematic's sounds. If the cinematic takes place some distance from the player, the author needs to move the player to a safe place near the action, which can become problematic.
When a player leans against a door, he can hear sounds on the other side. This is useful for overhearing private conversations or to track the progress of a guard patrolling a hallway. This is done by temporarily placing the location of the player's "ear" on the far side of the door, so as to exclude the door's sound occlusion settings from the volumes of the sounds reaching the "ear". So we already have a mechanism for moving the "ear".
In a similar manner, it might be possible to create a new entity that represents the player's "ear" for use during cinematics, in much the same way that a camera represents the player's "eyes".
By placing the new entity near the cinematic action, there would no longer be a need for moving the player, so he could stay safely where he was when the cinematic started. If the cinematic uses several cameras that span several rooms (i.e. the cinematic at the end of Somewhere Above the City), then the script controlling the cameras can also move the "cinematic ear".
I'm interested in researching this for 2.07, and would like to get your thoughts on other ways a "cinematic ear" might be used.
I don't recommend using it to get closer to non-cinematic conversations we encounter in missions, because "getting close enough to hear" is part of the mission's gameplay.