I'd have to say it'd be a neutral act -- act of god, so to speak.
Otherwise any number of scouting mechanisms are essentially unusable for fear of going rogue : Jotun scouts (which can easily win against low PD without being equipped), black servants, Pan's mages, and all of the stealthy unique demons / devils.
Edit : Hmm. Sneaking units supposedly don't get caught by PD less than 11, and I doubt the Jotun scout could win except against pitiful PD (Machaka perhaps). But the black servant, stealthy mages, and devils still could easily do so.