Free flow of information fosters innovation. Unfortunately this is just as true for endeavors most of us would rather didn’t exist. Krebs on Security has a good post about a Trojan which is using a more collaborative model to rapidly improve their product.
There is no denying the free flow of information helps evil people discover new methods, but the world is still a better place in the absence of secrecy. The majority of humans are not evil, despite how the news makes it seem, so even if fully 5% of the population were evil geniuses, which I think is quite high for both evil and geniuses, the other 95% of humanity (including many geniuses) could work with all available information to frustrate their efforts.
If anything, restricting access to information provides an environment where evil can flourish since it denies the ethical majority the chance to contribute, while evil will be business as usual. Like it or not there will always be a proportion of people working in an official capacity who are in fact evil as well, and secrecy only gives them more opportunity to do harm. In coping with evil, whether it’s cryptography or flu viruses, the more people who know the state of the art the better off we all are.