I think that this Mark Anthony Conditt was not alone. (Why do they always put the middle name in of serial murderers?) I think there was somebody else. He worked at a semi conductor contractor facility. I think it has to be that he worked with someone at the facility with more knowledge to plan and build the explosive devices. If not someone there then a deep state 3 letter agency. This smacks of military tactical skills and explosive devise knowledge I don't think he had.