I remember well searching for the book The Wizard War: British Scientific Intelligence, 1939-1945 (http://www.amazon.com/Wizard-War-Scientific-Intelligence-193...) in the summer of 1978, the year it came out (the library hadn't yet gotten its copy).
I'm almost finished reading a UK printing of The Deceivers: Allied Military Deception in the Second World War (http://www.amazon.com/Deceivers-Allied-Military-Deception-Se...) which was first published in 2005 and it comments that a lot of its material was only recently declassified. Prior to it the only detailed history was the bit known as The Man Who Never Was: World War II's Boldest Counter-Intelligence Operation (http://www.amazon.com/Man-Who-Never-Was-Counter-Intelligence...) from the '50s, which wildly overstates the importance this particular bit of deception used for the invasion of Sicily. It was one of many pieces which in total achieved complete success, but it and they don't hold a candle in "boldness" to FORTITUDE SOUTH and QUICKSILVER (http://en.wikipedia.org/wiki/Operation_Fortitude) which convinced Hitler and most of the Wehrmacht high command for well over a month that the Normandy landing was only a feint.
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