My parents let me have a shotgun when I was 12, and I kept it in my closet all through high school. I grew up around guns and hunting, and that is all a gun is to me, a tool that I keep in my closet. You need to put in a screw, you use a screwdriver. You need to hammer in a nail, you use a hammer. You need to put a hole in living flesh, you use a gun. It is just a tool.
It's a tool intended to end life, and must be handled with great presence and care. Lots of tools are dangerous and they each impact the human mind to some extent. Or rather, the human mind affects itself in response to the tools. It's usually not common for us to consider what sort of relationship we have with inanimate objects, but it's there for everything we interact with.
And I approve of your right to own firearms and use them as you will (as long as it's legal and you're never shooting or threatening another person), but to look at the link in OP and say, "Oh, this is useful information!" or even go further and practice searching for and murdering people in your house or another building is an exercise in fear.
I work hard to love people, and hope that it helps make me into the sort of person I want to be. If you want to be the sort of person that is suspicious of friends, family and neighbors, and cynical as a default; then that's good too. But don't tell me you're not affected by your relationship with your firearms.