I've been looking at different security issues that I should protect against, and came across this article, and I also find it hard to believe that I'll need to

I've been looking at different security issues that I should protect against, and came across this article, and I also find it hard to believe that I'll need to worry about this even though the author insists that it's doable. I wonder if this is more relavant in much higher profile attacks (cyberwar,etc) than in some webapp.