is Terminus Est really just a simple piece of hardware?

I plan on keeping my eye on descriptions of Terminus Est throughout the New Sun books, but something about how Dorcas described it when she was recounting to Severian what happened when he went down during the duel was interesting. I am wondering if the sword might be an artifact of much higher technology than Severian gives it credit for. Certainly it must be cleaned, oiled, and sharpened at various times in the book, but the description of a channel of liquid metal inside the blade seems to ring with the general "lostech" descriptions of many of the devices in the Mataquin Tower. When I get my hands on the book I will transcribe the passage where Dorcase describes using it to cut the avern that was about to bite Severian, it sounded like more was going on then simply a transfer of weight inside the blade.

The preparation of the blade's metal and the mercury is within the means of a medieval society, but drilling the channel down the finished center and fitting it with a threaded stopper would require something like a drill press, which would not be particularly unexpected in a place like Nessus, where enough old technology remains useful that mechanical limbs are not particularly remarkable.