Option for schedule parent tasks to automatically auto-calculate when it has sub tasks. If this option is enables, any time a subtask is added to a task, the parent task will be auto-calculated.
e.g. Gantt order task 1 has 1.1 added, 1 automatically becomes auto-calculated. If Task 1.1 has task 1.1.1 added as a sub task, 1.1 will automatically become auto calculated.
This would need to be an optional setting in the way that Keyboard Editing, Auto Replan and Include Weekends is as not all users will want to use this behaviour, wanting control over parent task progress and dates independently of child/subtasks.