*human conditioning: Despite being a dangerously strong and bloodthirsty killer who should under no circumstances be underestimated, there is still the fact that Jeff is just a normal human whose body still has its own limits. Like any other human being, he is still capable of being overpowered, outnumbered and outsmarted.
*Insanity: While he does have his clever and manipulative moments. It should be noted that Jeff is still insane, and such is prone to make unpredictable moves and decisions. Sometimes , Jeff will go straight for the kill instead of acting pragmatically and formulating plans.
