I am probably not the first person to experience this glitch, as I think it has happened to many of us without realizing it until after the fact. I know personally I had it happen long before I posted my original post in 2010 but had no idea how to reproduce the glitch, and it wasnt until around 2012 that I had tested it and figured it out. I searched high and low for anything regarding this glitch back at that time without any findings, however today I found a video dated 2009 of someone who also experienced the glitch, a 15 second video showing that they have 2 juggernogs, so I cant claim to have the first video of any kind displaying the visual aspect of the glitch; however it is clear from his video description he does not know how it happened and cannot do it again, as he isnt aware of the glitch having zero effect as far as boosting your juggs (his video description claims that it boosts it a little but not much). I am not trying to be a downer on his video, it's good that he recorded that clip when he had the chance, because I never recorded it when it happened to me the first several times it happened accidentally. At this point in time, it looks like I might be the first person to test and figure out the glitch, and be able to reproduce it, as I have uploaded a video a few days ago of the entire process from game start to end. I will be happy to stream it as well, and get more clips of doing it not only with juggernog but all perks~ after all, it does actually have an effect with quick revive, as my previous testing revealed. This might end up being more than simply a weird visual glitch, only time will tell....
Here is that video I referenced, which this guy recorded in 2009. It might be the earliest video of the glitch
https://youtu.be/S7sVAGPbr0A
Gotta give credit~