Group permission inheritance, with 1:1 to Active Directory?

Question

I am looking to add some groups to a subsite and wonder how the SharePoint permissions are cascaded for nested groups?

e.g. Is it least priveledge?

All_Users
|__Managers
   |__Request_Managers
   |__Order_Managers
   |__Processing_Managers
|__Users
   |__Request_Users
   |__Order_Users
   |__Processing_Users

i.e. If I add someone to Processing_Users then they should also get permissions to anywhere "Users" has permissions and also to "All_Users" (e.g. the site in general)

Finally, I'd like each group to have a 1:1 relationship to an AD group. Therefore add a user to the correct AD group and they automatically have permissions to the Site and all the areas relevant to the group.

Is that possible/feasible?

Answer 1

Just answered my own question...yet again to be let down by this appalling product:

Sharepoint groups cannot contain other SharePoint groups.

Well, thanks MS, that's very useful. Not.