It's difficult to see the parent/child hierarchy in the Task Name column of the task view of a project. The way it's spaced puts the starting letter of the parent even with the child and the arrow is small and lightly colored that it doesn't make a strong distinction.
My suggestion is to improve the visibility of the parent/child hierarchy.
Yes, I get lots of emails/tickets from people frustrated that they can't edit the percent complete- they don't realize it's because it's a roll-up parent task.
