Is it a skid? Is it an idiot? Nah, it is both. Skidiot is a skid that has surfaced up among their skid kind as so dumb, that they are known by their own skid kind as the idiot of the group.
Shikata was responding to a group of skids attempting to understand FTP... When the skidiot of the group piped up attempting to explain FTP to Shikata as a security device for automated file relocation for some reason...