I just had an experience of that, exactly an hour ago -- had the initiative from the get-go and never gave it back. The doorway to the place where I'm working is set back about 8 feet from the sidewalk, creating a nice short out-of-view corridor for the "street folks" to do drug deals, relieve themselves, light up their crack pipes, etc.; and part of my job is to head them off or stop them.
So I look up from where I'm sitting at the client services desk and, in the convex mirror set up by the door, I see a male/female couple tightly wrapped up with each other stagger in off the sidewalk, bounce off the walls a couple of times, then she's down on the concrete with him leaning over her, just the other side of the door's glass.
They were not being friendly. I couldn't really make out what she was trying to say, because he had a hand on her throat and was choking her, while he himself was yelling something along the line of, "Gimme mah f*&#ing money, *****!!!"
They never see me until I'm ready for them to.

I just suddenly and loudly smashed the door open, followed up by yelling at him to get the hell out of the doorway while "getting big on him". "Shock and awe" with continuing pressure. . .They were gone, FAST.
Sure, I could have grabbed the guy, done a citizen's arrest for assault and battery of the woman, cuffed him and called the police and waited until they got there, thereby creating a protracted and unpleasant situation for the clients and staff here. But in keeping with good taijutsu principles, I'm a believer that "less is more" -- less effort and fuss are good things. :uhyeah: