When trying to understand how Add To, Move To, and Duplicate functionality works between lists and how they are differentiated between each other, there is nothing intuitive about 'Add To' indicating the task is now a mirror of itself in multiple spaces. For spaces where a task is mirrored, but the users / permissions are different in each space (where users don't know it's mirrored), it is also not intuitive that a change in one place effects the other so we need some type of indicator or warnings about changes. The biggest problem is the risk of someone DELETING a task that is using Add To and it deleting from the other space with NO WARNING. It is not intuitive at all to have to check the task box, go to the bottom pop-up menu, select 'More...' and then 'Remove from List'. Instead, if someone attempts to delete a Mirrored Task, it should prompt to ask if the task should be deleted from all lists or only the current one.