No. So what happens is that when you cast Infernal Shade on a mob, the mob gets buffed but takes fire damage over time. One of the nodes (Soulfire) on the skill gives it an unlimited duration on minions, the Shifting Doom node gives it a 100 chance to reattach to a new minion after the first dies & the subjugation node gives it a 10% stacking damage buff for each second it’s attached (see the Soulfire node).
Edit: It looks as though the bug where the second minion didn’t take damage from the shade was fixed in 0.8.1c.
Not sure how that affects the stacking damage buff from Subjugation, it might be a bit of a nerf (that you need to summon your minions more) or it might be a significant nerf (that they don’t stack up the damage bonus from Subjugation to ridonculous levels).