Microsoft Knowledge Base Article 813338 contains the following summary:
For domains with many policies and domain
controllers with slow wide area network (WAN)
the SYSVOL share can take a
This is most noticeable when you promote
a new domain controller at a
location with slow connectivity or when you
restore of SYSVOL.
To speed up the process,
reduce the number of files and amount of data that must be
replicated in the
Because Administrative Templates (that is, .adm files) take up the most space in policies, remove them to significantly reduce the size of SYSVOL. For example, with the default Administrative Templates, each policy takes up 870 kilobytes (KB) of disk space. If you have 1,300 policies, you can reduce the size of SYSVOL from 1,100 megabytes (MB) to 35 MB (or 27 KB per policy).
You can use Group Policy settings to change the behavior of Group Policy Editor regarding .adm files in Microsoft Windows Server 2003. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
316977 Group Policy template behavior in Windows Server 2003