I guess that is true. The problem with the previous way is there was no possible way at all to make it so a moderator had different permissions in different forums.
Meaning, previously if a user moderated Forum A and Forum B, there was no way to make it so they could move topics in Forum A, but not move topics in Forum B.
So, it's true that if you wanted moderators to have different permissions in a specific forum then you'd need to be make a secondary group for that, it does end up being more flexible than the previous way.
What we are working on is being able to assign permissions on an individual user level as well. So once that's done, then it will open up more possibilities like doing what you mentioned.
