In this particular example he had a finite list of people he wanted to kill in either case, so if moderately athletic guy who's for-armed himself with a baseball bat and knife I'd expect him to be able to murder a person or small number of people with or without a gun.
As to someone who's really crazy and wants to kill as many people as possible, well, people who use bombs seem be much more deadly than people who use guns, so I'd be nervous about banning guns for fear of channeling them into less visceral but more deadly sorts of mayhem.
As to someone who's really crazy and wants to kill as many people as possible, well, people who use bombs seem be much more deadly than people who use guns, so I'd be nervous about banning guns for fear of channeling them into less visceral but more deadly sorts of mayhem.