Re Tom and his knitting needles: some countries expressly forbid carriage of knitting needles in hand luggage, I believe France is one. Others will only allow plastic or bamboo, require them to be sheathed and/ or may incur additional security. LGW and LHR seem to have no problem with taking them in hand luggage
https://www.gatwickairport.com/faqs/security/
https://www.heathrow.com/at-the-airp...ge-and-liquids
Tokyo airport may have different rules but my Japanese is very limited so can't check on the airport website!
TD was using circular needles in Tokyo which are primarily made of plastic - they would have been less of a security worry than a metal cutlery in First.