FWIW I have been developing apps in QB since 2002 and I have never felt that there was a use for that feature.
I always find a way to set those kind of permissions based on other techniques.
A very powerful technique if you need to control which record users see and don't wants to have a zillion Roles - never have a lot of roles !! - is to create a table of users where the key field is the userds.
Then in your details tables make a formula User field called [Current user] with a formula of user and then make the formula User(). Then make a relationship based on that field to the userid table and look up say a field for "department".
Then make a Custom Role Permission rule that regular users may only see / edit records where [Dept] is equal to [Current User- Dept]
So then you have one Role called "Users who are limited to their own department".
So one Role covers off 100 or 1000 departments.
