There's a certain kind of hell for those subtle tinkerers. I mean, it's really difficult for me to imagine a thought process that ends with an act like tiny putting pieces of paper over LAN cables, and putting them back in their jacks. The worst was when he abandoned paper and just tugged the cables out slightly enough for it not to make contact, but look more or less flush with all the other cable heads. A simple push would "click" it back into place, and for a while I just thought the RJ45 heads were bad. I thought I was going crazy, and people raised their eyebrows at me when this only seemed to happen to my servers.
Never happens where I work now. What a jerk.