This thread was from 2012 so you aren't hijacking anything.
Generally speaking, Genicanthus angels are more reef safe than any other angels. But, I have heard of occasion reports of them nipping at LPS, including my pair of larmark that are nipping at my open brain and acan from time to time. They are trying to eat the mucus and/or the waste from the mouth of LPS. This action doesn't seem to bother my LPS.