Parameters for -t (Restore original files)
-s <UNC path>         UNC path name of source folder, volume or fileserver
-e <ext list>         Optional. List of file types to restore.
                      Specify as comma separated list of file extensions,
                      for example: *.xls,*.doc,*.txt. Default is all file types: *.*
-d <UNC path>         Optional. Destination folder, volume or fileserver for restored files
-D <mm-dd-yyyy>       Optional. Only restore files archived after this date
-f                    Optional. Overwrite existing files and placeholders when names match.

What i take that to mean is if you delete a placeholder off of the server, we're assuming you don't want the file there to begin with
So i'm going to assume that the -f means only to restore files that have placeholders or files that already exist there

So if i have say

\\myserver\myShare\WordDoc1.doc
\\myserver\myShare\WordDoc2.doc
\\myserver\myShare\WordDoc3.doc

If i delete the shortcuts for WordDoc1 and WordDoc2 but i wanted to use FSAUtility to restore only the files that existed now in that share, i'd use the -f so that it only resotres WordDoc3.doc, as opposed to restoring WordDoc1 and WordDoc2 and i'd have to delete them over again.

But again I could be completely wrong and have misinterpreted it