What is the best method for updating bulk User ID's?
There is no VM:Secure command to do this.
The best way to deal with items in the directory that will be the same among many, is to put them in an included PROFILE.
That way, all changes to the PROFILE will be given to all users that include that profile in one swoop.
Users logged on when a change is made will need to log off and log back on to take advantage of any directory changes.