Security through obscurity came to mind when I was watching US Cyber commander, Keith Alexander, testify at the senate hearing yesterday. In this clip (<a href="http://www.c-spanvideo.org/clip/4455801" rel="nofollow">http://www.c-spanvideo.org/clip/4455801</a>) he seems to be making an argument for secrecy of the NSA's programs saying that it makes them more secure. From a purely engineering standpoint, this seems wrong to me.