properties vs. internal members

Hi,

I imagine this issue might have been actively discussed before.  But,
it doesn't seem to be symmetric in the way that properties and internal
members are treated in the spec.

For retrieving  a list of properties from a collection, DAV provides a
clear definition of how a server should return them in an XML doc.
As for retrieving a list of internal members from a collection which
is deemed an important operation to me, DAV only provides a vague
description on how it might work:

    GET when 
   applied to a collection may return the contents of an "index.html" 
   resource, a human-readable view of the contents of the collection, 
   or something else altogether. Hence it is possible that the result 
   of a GET on a collection will bear no correlation to the membership 
   of the collection. 

Can some one explain why internal members are treated in this way?  

Thanks in advance!


-Stanley