+1 for this one.
For many of my, ah, "less gifted" users the file manager only causes problems (like users deleting the public_html directory... ick).
But then this feature request gets very useful:
http://www.directadmin.com/forum/showthread.php?t=24128
Thanks, but I don't see how it's relevant to this thread. Here, we're talking about a feature to help prevent a specific avenue for a user possibly screwing something up.
In the thread you link, you're talking about fixing a range of problems after the fact. Interesting, but unrelated.