I have tried using displacement mirror images as decoys in the past, but no PC has ever attacked them in confusion - they have always gone directly for my PC. I believe that this in part because setting a PC hostile doesn't hostile the released mirror-images.
It would be nice if this could be done when using /c hostile or the player list to hostile the player.
You can not release them to make them a decoy, use the summon control tool to send them running in the other direction.
It's not perfect, but I'm not sure it should be.