Key quote: > The statisticians believed that the Germans, being Germans, had logically numbered their tanks in the order in which they were produced. The moral of the story is, never do anything that could give your opponent information, unless you're controlling what information they receive. It would be better to produce tanks with pseudo-random serial numbers, up to a maximum of whatever you want your enemy to thi…
Sometimes though, information denial is more of a pain in the ass than a gain. For all the intelligence directed at Nazi Germany during WWII, the outcome of the war was decided by a few Russian snowflakes, really.
Not by cracking Enigma?
http://en.wikipedia.org/wiki/Cryptanalysis_of_the_Enigma
And remember, "the war" was also being fought in the Pacific, also with a spectacular imbalance in cryptology strength between the Allies and the Axis.
http://en.wikipedia.org/wiki/Japanese_naval_codes
http://en.wikipedia.org/wiki/Magic_%28cryptography%29
In general, code-breaking had a lot to do with the outcome of the war.