When I assign a task to someone else, it disappears from my list. But I still want to know that I'm waiting on that. I find myself cloning the task first, then setting the status on the copy I keep to Delegated. (That doesn't tell me who I delegated it to, although that doesn't matter in my case.) Then when they complete the task we set up a complicated workflow where they assign it back to me so I know. Have a better way of tracking the things I've delegated and their status.