This would allow dynamic changes to a profile list in a single post in the compose window. The benefit would be in the case where you want the same content to be sent to almost all profiles in a group or all in the group plus some that aren't in the group.

You would select the profile list in the compose window and have an option to split it to display all the individual members. You could then delete ones you don't want and even add in some that are are new and not normally in the list.