Users not receiving email notification for task assignment

Ok, I've enabled "Send notifications to conversation feed" on the Plan, and while a task assignment is now showing up in Conversations, the person the task was assigned to still does not receive any notification; they aren't actually tagged in the message. If I comment on the task, I receive an email, but the person assigned does not.

So unless the person subscribes to the group/plan (e.g. turns on the "fire hose"), they won't know a task was assigned to them unless either 1) They check planner 2) they read through the whole group feed and see a task was assigned to them or 3) In a reply to the task someone manually @ mentions them. This seems ridiculously inefficient. Either they aren't notified at all or if they subscribe they get so much noise that the important information is lost.