Users of the Windows DFS (Distributed File System) may notice that their incremental or differential backups are nearly as large as their full backups.

When using DFS, you can also use a replication feature. This replication can potentially "touch" every file or nearly every file.
Thus, when using CFA to backup the volume, our software may think every file or nearly every file has changed.
This makes incrementals and differentials about the same size as a full backup.

While it is possible to disable DFS Replication, most admins will be very reluctant to for many reasons.

Resolution:
Enable "Preserve access times" and "only check modification times" on both the fileset and the inclusions. This minor change results in a much more reasonable incremental size.
The backups will only include new files and files that have been modified and ignore the updates made by DFS Replication (or by sharing certain public folders, etc.)