Thats not how this Game does Skewer. Enemies are not really dead when their HP drops to 0. If target 2 would be "killed" at the first hit, it could still receive other skewer hits. Its due to this why i dislike Skewer as each hit still grants pleasure points (Cleave > Skewer in pure). Before, dev did not really discard any enemy and its due to this why people experience slowdowns in Endless Waves.
Dickhead8888's problem is a simple one. He might not like it, but it's a feature that is mentioned in the Game.
Skewer Training 2 Edict: "Skewer MAY hit a third time" <--- It's not guaranteed.
With Skewer Training 2 you will have approximately 75% Chance to hit for a third time.
With Skewer Training 3, that chance is reduced to approximately 35% Chance but you gain a guaranteed +1 hit.
Skewer Specialization also grant a guaranteed +1 hit.