When all three XACML PDPs registered, PAP cycled each of them through the different groups and eventually left all of them in the "optimization" group, with none in the "monitoring" or "controlloop" groups.

Possibly related issue reported by Jorge: I ran into an issue where I restarted both drools and pap, and seems that pap was not reissuing the state change message to go active, it goes by the previous state in the database before restarting the drools comes up, seems like.