It’s not the first time I’ve heard people complain about it, while for me it never been a big deal at all.
Yes, it does spread from time to time and appear in different spots, but it never stung any other coral, including quite a wide variety of acros which usually instantly kill the Poceliphora if they touch each other.
And as already been mentioned here, I also just grow them out a little and break them off if they bother me and they never grow in that spot again.
I do wonder though - maybe there is a type that is more aggressive (in terms of stinging) than the one I own? Because I guess that’s the main issue you really have with it.