I never found out what happened internally on that engine. About the time that I had read that message I stopped looking at the newsgroup and stayed right here. But I imagine that a chunk of porcelin rattling around in the chamber could do some damage if big enough. Porcelin, is pretty dense stuff, in fact the porcelin part of a plug will break a car window.
Shortly after asking my question, I pulled my plats and went to Bosch copper core, AutoZone had a sale on them for something like 59 cents a pop. I had a slight miss at idle, and with changing to copper cores the miss was eliminated.
73 280 SEL 4.5