I'm not sure how to perform any kind of match making based on the resources IndividualDiskSpace, and similarly, the 
DiskSpace element of the FileSystem element. 

For both, is the amount of space:

1. The size of the volume
2. The number of free bytes on the volume
3. The number of free bytes available to the user on the volume. 

If 3, how is it proposed to make this calculation efficiently. 


For IndividualDiskSpace, is this:

1. An aggregation of all locally mounted volumes? 
2. Does it include network volumes? 
3. Is it calculated before or after FileSystem mounts happen (thus affecting the number if network volumes are also 
considered). 

Because of these questions, it's not clear to me that this element has any use (given that I can be specific about 
volume disk requirements using FileSystem).