For Radio controlled Drones with active operators, yes.   However, it would be relatively trivial to convert a fleet of drones to converge on a location with predetermined flight paths.  It could be done with or without GPS.  This is a little more complex, requires more planning, and some special modifications... but a swarm attack could could take 10, 15, or 20 drones and send each to a slightly different programmed location to create a kill zone.  Scary stuff.  I'd never thought of it until I read this article.