Apparently, when one moves a linked Nether portal, it doesn't like it.
So when Key decided he wanted his Nether portal moved, and LSO moved it, it created a problem. Resulting in a Nether portal being generated in Simpson's mines. I removed it, but when I placed a new nether portal, went through, and came back... guess where I was, and what was back? Yep, Nether Portal in Simpson's mines.
If any of the mods, admins, or anybody with Nether portal experience could fix this, please, do so. I have no clue how to manipulate this.
YEah, portals are wacky. Even if you get a good system for predicting where your portals will open in real space or the nether, their seems to be all sorts of bugs associated with portal formation and portal linking. two real space portals linked to one nether world portal, that kind of thing are common.