That almost certainly cannot work. You'll have false negatives, people will sneak the words of synonyms in (just think of how many web forums has people saying

That almost certainly cannot work. You'll have false negatives, people will sneak the words of synonyms in (just think of how many web forums has people saying "fcuk", or "f*ck"), and false positives, legitimate transactions being banned. Will anyone from scunthorpe be able to use it?