I just posted a video: uctv.tv/shows/Progressive-S... which is an interview with an expert in the PSP field, and when she said excess contact with metals combined with the weirdness of tau protein seems to create an environment to produce PSP (liberally paraphrased haha,) I nearly fell out of my seat!!! because my dad, my dear ol' Daddy was a SHEET METAL WORKER all his life. He owned his own successful company after working fulltime for employers for many years, all sheet metal. Who knew! Now, my brother is 56 has worked sheet metal all his life and so does his son. I wonder if the harm is done by particles in the air when the metals are cut or if it's by touch or WHAT. It's scary to think something so random and off the wall could be a major contributing factor in the nightmare of PSP. Anyone else????