[Zope] Simpleton requests help - what's this mapping malarkey ?:)

[chas]

I'm feeling kind of dumb here - perhaps I'm getting distracted by
the terminology used but what's this "mapping" of permissions ? 

I've checked the ZCMG but that only deals with users/roles/permissions
which is fairly straight-forward and intuitive. Were these permission
mappings added in Zope 2.0 or is documentation hiding somewhere ?

eg. Ok, so let's look at a typical "define permissions" page :

    - Access contents information      <disabled>
    - Change DTML Methods              <disabled>
    - Change permissions               <disabled>
    - Change proxy roles               <disabled>
    - Delete objects                   <disabled>
    - FTP access                       <disabled>
    - Manage properties                <disabled>
    - View                             <view>
    - View management screens          <disabled>

OK, so "view management screens" is now disable and nobody can 
view them. Fair enough.  But say I want to enable them, why 
would I want to map "view management screens" to anything
other than, er, "view management screens" ? And where is the 
correlation between this action and a user's identity ?

Another example: anonymous users call this dtml-method; this 
method then changes the properties of the zclass. So, I go to
the pulldown menu opposite "manage properties" and roger me
relentlessly if "manage properties" doesn't just look like
the appropriate choice ! The mind boggles - I'm going nuts.
What am I supposed to do with this ?

As I said, roles/users/permissions make sense but these make
as much sense as a bucketful of number 2's.

chas