I had not seen Doc Hoff for a while so I just assumed he had met his demise out in the wastes. Imagine my surprise when I was doing the Waters of Life quest I found him and his whole caravan in the silt pump pipes under the Jefferson Memorial. He was fully functional and I traded with him and had him repair some of my things. After I continued on to fight the Enclave his caravan followed me through the pipe, into the basemant and into the gift shop area. I left him at the exit door to the wasteland while I continued on to the Taft Tunnels. I hope he can find his way out the door and continue his travels.
Has this happened to anyone else or is this a one of a kind glitch?