That s an extremely selective quotation from the nutshell text The essay which I originally wrote so I m pretty familiar with it gives three basic check points to verify whether it s likely that an xkcd reference is helpful this reference meets none of them It is at best a trivial and non free illustration of an SQL injection attack which has its own article anyway People are prone to arguing that a given xkcd strip provides some unique insight into a subject when this is usually extremely subjective Were this actually the case for a given reference then one would imagine that some third party would pick up on this in a reliable source That hasn t happened here so it seems like nothing more than one Wikipedia editor s personal judgement WP EL specifically notes when external links are appropriate and again this link doesn t meet those guidelines as applied to the rest of the encyclopedia Chris Cunningham not at work talk