Umm, no, this is not practical and has a major caveat. It will not work unless the server is fully stopped while doing it. If the server is running, it will 1) not be loaded and 2) be overwritten when the server shuts down.
True if and only if 'exec banned.cfg' is missing from mapchangecfgfile.
When 'exec banned.cfg' does not show in server.cfg nobody is banned on launch or mapchange. Using writeid will wipe entire file.
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