Direct editing of filter files not supported
Guardian does not support direct editing of the filter files "filters.txt" and "filters_human.txt".
When running, Guardian ignores the "filters_human.txt" file and references only the "filters.txt" file. The latter file contains a condensed copy of the rules, with all invalid rules and comments stripped out.
Based on this, one might wish to directly edit the "filters.txt" file, but one shouldn't because that file will be overwritten whenever filters are viewed and saved in the Guardian admin mode. In admin mode, Guardian displays the contents of the "filters_human.txt" file. When saving, the contents are validated. All text is saved back to the "filters_human.txt" file, and all valid condensed rules are written to the "filters.txt" file. Any customizations made directly to the "filters.txt" file would be overwritten in this step.
Likewise, direct edits to the "filters_human.txt" file can be made, but they will have no effect on the running of Guardian until the web-based admin page is used to view and save the changes, at which point the live file "filters.txt" will be updated.
"Direct editing of filter files not supported" http://www.xav.com/scripts/guardian/help/1023.html