I used a Shinobi to ambush an enemy pod with an Arc Blade. When they scampered, one of the Bladestorm actions stunned an enemy. The enemy's movement was interrupted, the game lagged for about 15 seconds, the enemy was marked as "Stunned: 2", the game lagged for another 20 seconds, and then the enemy stood up ... unstunned.
I've found this to be repeatable.