Tech Erps Ping!
Probably trying to slip information to their Al Queda butt buddies in a deniable way.
If this was a bungle, it was a bad bungle. This same method could, however, also be used to mislead enemy forces by leaking “secret” information that just plain is not true. Sounds like something James Bond would do, but I don’t know if the current British defence [sic] has the brains.
The british navy has secrets??
This is stupid. Classification requirements include rules for declassifying information, and that would include methods of scanning documents for classified information if the documents were not pure text.
The simplest way to accomplish correct redaction is to print out the document, redact it, and scan it back in.