Yeah, you do realize that you're just assuming how it's going to plan out, don't you? Operating on just assumptions, a human being will almost always find his plan to be brilliant and perfectly workable. Humans don't have very good physics processors in their head.
That's why the obese man sitting on the couch eating pork rinds screams and calls an idiot the football player who fumbled. They vastly underestimate the physical difficulty of doing things they want done - be it stabbing, "throwing their whole body" into a man wielding a FUCKING BASEBALL BAT, or running to a painted line.
Even unarmed I don't think killing someone with a knife would be as easy as with a baseball bat, unless the person were unaware at the beginning.