How accurate is 'The Imitation Game'?

by Shadoowmass

In the movie, it is said that Alan Turing and his team, using decrypted Enigma messages, that they 'decided who would die and who would live' by relaying what messages they could afford to to the army, determined using statistics. How much of this is true?

Killfile

Kinda, though obviously the decision making apparatus extended beyond the cryptographers who broke the code mathematically. Once the British (and the Americans, who helped out enormously with the computational grunt-work of the process) had a... let's call it "industrial"... process in place to attack the Enigma intercepts on a day to day basis the work on the program boiled down to preserving secrecy.

That meant compartmentalizing the information about what they were doing -- intercepts were, for example, decrypted and translated by distinct groups with minimal cross-talk -- but also not tipping their hand to the Germans.

So intelligence from Enigma -- "Ultra" Intelligence -- was carefully reviewed before it was acted upon. Actions which might reveal that Enigma had been broken: attacking a submarine that was not where it was supposed to be and was radioing in a new position, for example, required some kind of cover. A reconnisance plane would be dispatched along a path which would overfly the submarine (the crew didn't know that their mission was just a fig-leaf) or, in one case, the British sent a message in a code they knew the Germans had broken, congratulating a fictitious spy for intelligence that lead to the sinking of a German convoy.

To some extent, the decisions when to use Enigma and when the source was more important than some potential exploitation are what is alluded to in the film -- deciding who lived and died. But the decision making apparatus was not a bunch of academics and puzzle geeks in Bletchley Park but the very highest levels of the Allied Governments and Military (excluding the Soviets, of course, who everyone else tried to keep in the dark on the whole thing.)