I have survived several bayonet and melee attacks, while also sometimes needing two hits to kill (if I didn't get killed after the first hit).
So it's definately no surefire instakill as it is in CoD.
Additionally, unless you're off against another boltie, or the enemie panics upon seeing your dashing fury, it's actually quite hard to get close enough to land a blow.
Which makes the whole affair quite satisfying, even without taking the freudian implication of inserting a long, hard object inside somebody else into account...